From 8da1887d45032bb37438b080f1d80a305910b9a0 Mon Sep 17 00:00:00 2001
From: Simon Cropp <simon.cropp@gmail.com>
Date: Sun, 11 Oct 2026 23:18:14 +1100
Subject: [PATCH 1/2] Fix NullReferenceException in span *AnyExcept with null
 elements

---
 api_list.include.md                           | 48 +++++++++----------
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 42 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../net47/Polyfill_Memory_IndexOfAnyExcept.cs | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../net48/Polyfill_Memory_IndexOfAnyExcept.cs | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../Polyfill_Memory_ContainsAnyExcept.cs      | 40 +++++++++++-----
 .../Polyfill_Memory_IndexOfAnyExcept.cs       | 29 ++++++-----
 .../Polyfill_Memory_LastIndexOfAnyExcept.cs   | 29 ++++++-----
 .../PolyfillTests_Memory_ContainsAnyExcept.cs | 42 ++++++++++++++++
 .../PolyfillTests_Memory_IndexOfAnyExcept.cs  | 36 ++++++++++++++
 ...lyfillTests_Memory_LastIndexOfAnyExcept.cs | 36 ++++++++++++++
 59 files changed, 1284 insertions(+), 684 deletions(-)

diff --git a/api_list.include.md b/api_list.include.md
index f8bb02f0..6f1374f2 100644
--- a/api_list.include.md
+++ b/api_list.include.md
@@ -1057,10 +1057,10 @@
  * `int CommonPrefixLength<T>(ReadOnlySpan<T>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.commonprefixlength?view=net-11.0#system-memoryextensions-commonprefixlength-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
  * `bool Contains<T>(T, IEqualityComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.contains?view=net-11.0#system-memoryextensions-contains-1(system-readonlyspan((-0))-0-system-collections-generic-iequalitycomparer((-0))))
  * `bool Contains<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.contains?view=net-11.0#system-memoryextensions-contains-1(system-readonlyspan((-0))-0))
- * `bool ContainsAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
- * `bool ContainsAnyExcept<T>(T, T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0-0-0))
- * `bool ContainsAnyExcept<T>(T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0-0))
- * `bool ContainsAnyExcept<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0))
+ * `bool ContainsAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
+ * `bool ContainsAnyExcept<T>(T, T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0-0-0))
+ * `bool ContainsAnyExcept<T>(T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0-0))
+ * `bool ContainsAnyExcept<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0))
  * `bool ContainsAnyExceptInRange<T>(T, T) where T : IComparable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexceptinrange?view=net-11.0#system-memoryextensions-containsanyexceptinrange-1(system-readonlyspan((-0))-0-0))
  * `bool ContainsAnyInRange<T>(T, T) where T : IComparable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyinrange?view=net-11.0#system-memoryextensions-containsanyinrange-1(system-readonlyspan((-0))-0-0))
  * `int CountAny<T>(ReadOnlySpan<T>, IEqualityComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.countany?view=net-11.0#system-memoryextensions-countany-1(system-readonlyspan((-0))-system-readonlyspan((-0))-system-collections-generic-iequalitycomparer((-0))))
@@ -1069,14 +1069,14 @@
  * `bool EndsWith<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.endswith?view=net-11.0#system-memoryextensions-endswith-1(system-readonlyspan((-0))-0))
  * `int IndexOf<T>(T, IEqualityComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexof?view=net-11.0#system-memoryextensions-indexof-1(system-readonlyspan((-0))-0-system-collections-generic-iequalitycomparer((-0))))
  * `int IndexOfAny<T>(ReadOnlySpan<T>, IEqualityComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.countany?view=net-11.0#system-memoryextensions-countany-1(system-readonlyspan((-0))-system-buffers-searchvalues((-0))))
- * `int IndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
- * `int IndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0-0-0))
- * `int IndexOfAnyExcept<T>(T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0-0))
- * `int IndexOfAnyExcept<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0))
- * `int LastIndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
- * `int LastIndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0-0-0))
- * `int LastIndexOfAnyExcept<T>(T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0-0))
- * `int LastIndexOfAnyExcept<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0))
+ * `int IndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
+ * `int IndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0-0-0))
+ * `int IndexOfAnyExcept<T>(T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0-0))
+ * `int IndexOfAnyExcept<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0))
+ * `int LastIndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
+ * `int LastIndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0-0-0))
+ * `int LastIndexOfAnyExcept<T>(T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0-0))
+ * `int LastIndexOfAnyExcept<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0))
  * `T? Max<T>(IComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.max?view=net-11.0#system-memoryextensions-max-1(system-readonlyspan((-0))-system-collections-generic-icomparer((-0))))
  * `T? Max<T>()` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.max?view=net-11.0#system-memoryextensions-max-1(system-readonlyspan((-0))))
  * `T? Min<T>(IComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.min?view=net-11.0#system-memoryextensions-min-1(system-readonlyspan((-0))-system-collections-generic-icomparer((-0))))
@@ -1235,20 +1235,20 @@
  * `int CommonPrefixLength<T>(ReadOnlySpan<T>, IEqualityComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.commonprefixlength?view=net-11.0#system-memoryextensions-commonprefixlength-1(system-span((-0))-system-readonlyspan((-0))-system-collections-generic-iequalitycomparer((-0))))
  * `int CommonPrefixLength<T>(ReadOnlySpan<T>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.commonprefixlength?view=net-11.0#system-memoryextensions-commonprefixlength-1(system-span((-0))-system-readonlyspan((-0))))
  * `bool Contains<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.contains?view=net-11.0#system-memoryextensions-contains-1(system-span((-0))-0))
- * `bool ContainsAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-system-readonlyspan((-0))))
- * `bool ContainsAnyExcept<T>(T, T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0-0-0))
- * `bool ContainsAnyExcept<T>(T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0-0))
- * `bool ContainsAnyExcept<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0))
+ * `bool ContainsAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-system-readonlyspan((-0))))
+ * `bool ContainsAnyExcept<T>(T, T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0-0-0))
+ * `bool ContainsAnyExcept<T>(T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0-0))
+ * `bool ContainsAnyExcept<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0))
  * `bool ContainsAnyExceptInRange<T>(T, T) where T : IComparable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexceptinrange?view=net-11.0#system-memoryextensions-containsanyexceptinrange-1(system-span((-0))-0-0))
  * `bool ContainsAnyInRange<T>(T, T) where T : IComparable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyinrange?view=net-11.0#system-memoryextensions-containsanyinrange-1(system-span((-0))-0-0))
- * `int IndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-system-readonlyspan((-0))))
- * `int IndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0-0-0))
- * `int IndexOfAnyExcept<T>(T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0-0))
- * `int IndexOfAnyExcept<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0))
- * `int LastIndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-system-readonlyspan((-0))))
- * `int LastIndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0-0-0))
- * `int LastIndexOfAnyExcept<T>(T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0-0))
- * `int LastIndexOfAnyExcept<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0))
+ * `int IndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-system-readonlyspan((-0))))
+ * `int IndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0-0-0))
+ * `int IndexOfAnyExcept<T>(T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0-0))
+ * `int IndexOfAnyExcept<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0))
+ * `int LastIndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-system-readonlyspan((-0))))
+ * `int LastIndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0-0-0))
+ * `int LastIndexOfAnyExcept<T>(T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0-0))
+ * `int LastIndexOfAnyExcept<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0))
  * `void Sort<T>(Comparison<T>)`
  * `void Sort<T>() where T : IComparable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.sort?view=net-11.0#system-memoryextensions-sort-1(system-span((-0))))
 
diff --git a/src/Polyfill/Polyfill_Memory_ContainsAnyExcept.cs b/src/Polyfill/Polyfill_Memory_ContainsAnyExcept.cs
index 6b1d135c..9c7e462b 100644
--- a/src/Polyfill/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Polyfill/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,17 +3,19 @@
 namespace Polyfills;
 
 using System;
+using System.Collections.Generic;
 
 static partial class Polyfill
 {
     /// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0)
     public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-        where T : IEquatable<T>
+        where T : IEquatable<T>?
     {
+        var comparer = EqualityComparer<T>.Default;
         for (var i = 0; i < span.Length; i++)
         {
-            if (!span[i].Equals(value))
+            if (!comparer.Equals(span[i], value))
             {
                 return true;
             }
@@ -25,12 +27,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
     /// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0-0)
     public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-        where T : IEquatable<T>
+        where T : IEquatable<T>?
     {
+        var comparer = EqualityComparer<T>.Default;
         for (var i = 0; i < span.Length; i++)
         {
             var item = span[i];
-            if (!item.Equals(value0) && !item.Equals(value1))
+            if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
             {
                 return true;
             }
@@ -42,12 +45,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
     /// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0-0-0)
     public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-        where T : IEquatable<T>
+        where T : IEquatable<T>?
     {
+        var comparer = EqualityComparer<T>.Default;
         for (var i = 0; i < span.Length; i++)
         {
             var item = span[i];
-            if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+            if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
             {
                 return true;
             }
@@ -59,11 +63,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
     /// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0)))
     public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-        where T : IEquatable<T>
+        where T : IEquatable<T>?
     {
+        var comparer = EqualityComparer<T>.Default;
         for (var i = 0; i < span.Length; i++)
         {
-            if (!values.Contains(span[i]))
+            if (!ContainsValue(values, span[i], comparer))
             {
                 return true;
             }
@@ -75,26 +80,39 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
     /// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0)
     public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-        where T : IEquatable<T> =>
+        where T : IEquatable<T>? =>
         ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 
     /// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0-0)
     public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-        where T : IEquatable<T> =>
+        where T : IEquatable<T>? =>
         ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 
     /// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0-0-0)
     public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-        where T : IEquatable<T> =>
+        where T : IEquatable<T>? =>
         ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 
     /// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-system-readonlyspan((-0)))
     public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-        where T : IEquatable<T> =>
+        where T : IEquatable<T>? =>
         ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+
+    static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+    {
+        for (var i = 0; i < values.Length; i++)
+        {
+            if (comparer.Equals(values[i], value))
+            {
+                return true;
+            }
+        }
+
+        return false;
+    }
 }
 
 #endif
diff --git a/src/Polyfill/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Polyfill/Polyfill_Memory_IndexOfAnyExcept.cs
index a4d9779b..ee3bd577 100644
--- a/src/Polyfill/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Polyfill/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,17 +3,19 @@
 namespace Polyfills;
 
 using System;
+using System.Collections.Generic;
 
 static partial class Polyfill
 {
     /// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0)
     public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-        where T : IEquatable<T>
+        where T : IEquatable<T>?
     {
+        var comparer = EqualityComparer<T>.Default;
         for (var i = 0; i < span.Length; i++)
         {
-            if (!span[i].Equals(value))
+            if (!comparer.Equals(span[i], value))
             {
                 return i;
             }
@@ -25,12 +27,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
     /// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0-0)
     public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-        where T : IEquatable<T>
+        where T : IEquatable<T>?
     {
+        var comparer = EqualityComparer<T>.Default;
         for (var i = 0; i < span.Length; i++)
         {
             var item = span[i];
-            if (!item.Equals(value0) && !item.Equals(value1))
+            if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
             {
                 return i;
             }
@@ -42,12 +45,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
     /// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0-0-0)
     public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-        where T : IEquatable<T>
+        where T : IEquatable<T>?
     {
+        var comparer = EqualityComparer<T>.Default;
         for (var i = 0; i < span.Length; i++)
         {
             var item = span[i];
-            if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+            if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
             {
                 return i;
             }
@@ -59,11 +63,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
     /// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0)))
     public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-        where T : IEquatable<T>
+        where T : IEquatable<T>?
     {
+        var comparer = EqualityComparer<T>.Default;
         for (var i = 0; i < span.Length; i++)
         {
-            if (!values.Contains(span[i]))
+            if (!ContainsValue(values, span[i], comparer))
             {
                 return i;
             }
@@ -75,25 +80,25 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
     /// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0)
     public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-        where T : IEquatable<T> =>
+        where T : IEquatable<T>? =>
         IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 
     /// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0-0)
     public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-        where T : IEquatable<T> =>
+        where T : IEquatable<T>? =>
         IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 
     /// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0-0-0)
     public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-        where T : IEquatable<T> =>
+        where T : IEquatable<T>? =>
         IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 
     /// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-system-readonlyspan((-0)))
     public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-        where T : IEquatable<T> =>
+        where T : IEquatable<T>? =>
         IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 
diff --git a/src/Polyfill/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Polyfill/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 0e0f8d9e..18ead43c 100644
--- a/src/Polyfill/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Polyfill/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,17 +3,19 @@
 namespace Polyfills;
 
 using System;
+using System.Collections.Generic;
 
 static partial class Polyfill
 {
     /// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0)
     public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-        where T : IEquatable<T>
+        where T : IEquatable<T>?
     {
+        var comparer = EqualityComparer<T>.Default;
         for (var i = span.Length - 1; i >= 0; i--)
         {
-            if (!span[i].Equals(value))
+            if (!comparer.Equals(span[i], value))
             {
                 return i;
             }
@@ -25,12 +27,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
     /// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0-0)
     public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-        where T : IEquatable<T>
+        where T : IEquatable<T>?
     {
+        var comparer = EqualityComparer<T>.Default;
         for (var i = span.Length - 1; i >= 0; i--)
         {
             var item = span[i];
-            if (!item.Equals(value0) && !item.Equals(value1))
+            if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
             {
                 return i;
             }
@@ -42,12 +45,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
     /// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0-0-0)
     public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-        where T : IEquatable<T>
+        where T : IEquatable<T>?
     {
+        var comparer = EqualityComparer<T>.Default;
         for (var i = span.Length - 1; i >= 0; i--)
         {
             var item = span[i];
-            if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+            if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
             {
                 return i;
             }
@@ -59,11 +63,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
     /// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0)))
     public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-        where T : IEquatable<T>
+        where T : IEquatable<T>?
     {
+        var comparer = EqualityComparer<T>.Default;
         for (var i = span.Length - 1; i >= 0; i--)
         {
-            if (!values.Contains(span[i]))
+            if (!ContainsValue(values, span[i], comparer))
             {
                 return i;
             }
@@ -75,25 +80,25 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
     /// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0)
     public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-        where T : IEquatable<T> =>
+        where T : IEquatable<T>? =>
         LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 
     /// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0-0)
     public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-        where T : IEquatable<T> =>
+        where T : IEquatable<T>? =>
         LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 
     /// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0-0-0)
     public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-        where T : IEquatable<T> =>
+        where T : IEquatable<T>? =>
         LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 
     /// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
     //Link: https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-system-readonlyspan((-0)))
     public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-        where T : IEquatable<T> =>
+        where T : IEquatable<T>? =>
         LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 
diff --git a/src/Split/net461/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/net461/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/net461/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/net461/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/net461/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/net461/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/net461/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/net461/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net461/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/net461/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/net461/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/net461/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net462/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/net462/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/net462/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/net462/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/net462/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/net462/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/net462/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/net462/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net462/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/net462/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/net462/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/net462/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net47/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/net47/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/net47/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/net47/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/net47/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/net47/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/net47/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/net47/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net47/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/net47/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/net47/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/net47/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net471/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/net471/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/net471/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/net471/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/net471/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/net471/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/net471/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/net471/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net471/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/net471/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/net471/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/net471/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net472/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/net472/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/net472/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/net472/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/net472/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/net472/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/net472/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/net472/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net472/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/net472/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/net472/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/net472/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net48/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/net48/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/net48/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/net48/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/net48/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/net48/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/net48/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/net48/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net48/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/net48/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/net48/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/net48/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net481/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/net481/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/net481/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/net481/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/net481/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/net481/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/net481/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/net481/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net481/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/net481/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/net481/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/net481/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net5.0/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/net5.0/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/net5.0/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/net5.0/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/net5.0/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/net5.0/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/net5.0/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/net5.0/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net5.0/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/net5.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/net5.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/net5.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net6.0/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/net6.0/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/net6.0/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/net6.0/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/net6.0/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/net6.0/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/net6.0/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/net6.0/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net6.0/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/net6.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/net6.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/net6.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/net7.0/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/net7.0/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/net7.0/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/net7.0/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/netcoreapp2.0/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/netcoreapp2.0/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/netcoreapp2.0/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/netcoreapp2.0/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/netcoreapp2.0/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/netcoreapp2.0/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/netcoreapp2.0/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/netcoreapp2.0/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netcoreapp2.0/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/netcoreapp2.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/netcoreapp2.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/netcoreapp2.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netcoreapp2.1/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/netcoreapp2.1/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/netcoreapp2.1/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/netcoreapp2.1/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/netcoreapp2.1/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/netcoreapp2.1/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/netcoreapp2.1/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/netcoreapp2.1/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netcoreapp2.1/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/netcoreapp2.1/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/netcoreapp2.1/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/netcoreapp2.1/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netcoreapp2.2/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/netcoreapp2.2/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/netcoreapp2.2/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/netcoreapp2.2/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/netcoreapp2.2/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/netcoreapp2.2/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/netcoreapp2.2/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/netcoreapp2.2/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netcoreapp2.2/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/netcoreapp2.2/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/netcoreapp2.2/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/netcoreapp2.2/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netcoreapp3.0/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/netcoreapp3.0/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/netcoreapp3.0/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/netcoreapp3.0/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/netcoreapp3.0/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/netcoreapp3.0/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/netcoreapp3.0/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/netcoreapp3.0/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netcoreapp3.0/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/netcoreapp3.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/netcoreapp3.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/netcoreapp3.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netcoreapp3.1/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/netcoreapp3.1/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/netcoreapp3.1/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/netcoreapp3.1/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/netcoreapp3.1/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/netcoreapp3.1/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/netcoreapp3.1/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/netcoreapp3.1/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netcoreapp3.1/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/netcoreapp3.1/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/netcoreapp3.1/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/netcoreapp3.1/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netstandard2.0/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/netstandard2.0/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/netstandard2.0/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/netstandard2.0/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/netstandard2.0/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/netstandard2.0/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/netstandard2.0/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/netstandard2.0/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netstandard2.0/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/netstandard2.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/netstandard2.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/netstandard2.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netstandard2.1/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/netstandard2.1/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/netstandard2.1/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/netstandard2.1/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/netstandard2.1/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/netstandard2.1/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/netstandard2.1/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/netstandard2.1/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/netstandard2.1/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/netstandard2.1/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/netstandard2.1/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/netstandard2.1/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/uap10.0/Polyfill_Memory_ContainsAnyExcept.cs b/src/Split/uap10.0/Polyfill_Memory_ContainsAnyExcept.cs
index cda3e7d0..6b67b6cf 100644
--- a/src/Split/uap10.0/Polyfill_Memory_ContainsAnyExcept.cs
+++ b/src/Split/uap10.0/Polyfill_Memory_ContainsAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return true;
 			}
@@ -20,12 +22,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return true;
 			}
@@ -34,12 +37,13 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return true;
 			}
@@ -48,11 +52,12 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T v
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return true;
 			}
@@ -61,19 +66,30 @@ public static bool ContainsAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<
 	}
 	/// <summary>Searches for any value other than the specified <paramref name="value"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for any value other than the specified <paramref name="values"/>.</summary>
 	public static bool ContainsAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		ContainsAnyExcept((ReadOnlySpan<T>)span, values);
+	static bool ContainsValue<T>(ReadOnlySpan<T> values, T value, EqualityComparer<T> comparer)
+	{
+		for (var i = 0; i < values.Length; i++)
+		{
+			if (comparer.Equals(values[i], value))
+			{
+				return true;
+			}
+		}
+		return false;
+	}
 }
 #endif
diff --git a/src/Split/uap10.0/Polyfill_Memory_IndexOfAnyExcept.cs b/src/Split/uap10.0/Polyfill_Memory_IndexOfAnyExcept.cs
index d49c931b..565244a8 100644
--- a/src/Split/uap10.0/Polyfill_Memory_IndexOfAnyExcept.cs
+++ b/src/Split/uap10.0/Polyfill_Memory_IndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T val
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = 0; i < span.Length; i++)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int IndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T>
 	}
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int IndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		IndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Split/uap10.0/Polyfill_Memory_LastIndexOfAnyExcept.cs b/src/Split/uap10.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
index 591af601..06e3f381 100644
--- a/src/Split/uap10.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Split/uap10.0/Polyfill_Memory_LastIndexOfAnyExcept.cs
@@ -3,15 +3,17 @@
 #if FeatureMemory
 namespace Polyfills;
 using System;
+using System.Collections.Generic;
 static partial class Polyfill
 {
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!span[i].Equals(value))
+			if (!comparer.Equals(span[i], value))
 			{
 				return i;
 			}
@@ -20,12 +22,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value)
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1))
 			{
 				return i;
 			}
@@ -34,12 +37,13 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
 			var item = span[i];
-			if (!item.Equals(value0) && !item.Equals(value1) && !item.Equals(value2))
+			if (!comparer.Equals(item, value0) && !comparer.Equals(item, value1) && !comparer.Equals(item, value2))
 			{
 				return i;
 			}
@@ -48,11 +52,12 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, T value0, T
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T>
+		where T : IEquatable<T>?
 	{
+		var comparer = EqualityComparer<T>.Default;
 		for (var i = span.Length - 1; i >= 0; i--)
 		{
-			if (!values.Contains(span[i]))
+			if (!ContainsValue(values, span[i], comparer))
 			{
 				return i;
 			}
@@ -61,19 +66,19 @@ public static int LastIndexOfAnyExcept<T>(this ReadOnlySpan<T> span, ReadOnlySpa
 	}
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="value"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/> or <paramref name="value1"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1);
 	/// <summary>Searches from the end for the first index of any value other than <paramref name="value0"/>, <paramref name="value1"/>, or <paramref name="value2"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, T value0, T value1, T value2)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, value0, value1, value2);
 	/// <summary>Searches from the end for the first index of any value other than the specified <paramref name="values"/>.</summary>
 	public static int LastIndexOfAnyExcept<T>(this Span<T> span, ReadOnlySpan<T> values)
-		where T : IEquatable<T> =>
+		where T : IEquatable<T>? =>
 		LastIndexOfAnyExcept((ReadOnlySpan<T>)span, values);
 }
 #endif
diff --git a/src/Tests/PolyfillTests_Memory_ContainsAnyExcept.cs b/src/Tests/PolyfillTests_Memory_ContainsAnyExcept.cs
index ee1adb42..078af690 100644
--- a/src/Tests/PolyfillTests_Memory_ContainsAnyExcept.cs
+++ b/src/Tests/PolyfillTests_Memory_ContainsAnyExcept.cs
@@ -108,4 +108,46 @@ public Task Span_ContainsAnyExcept_SingleValue()
 
         return Task.CompletedTask;
     }
+
+    [Test]
+    public async Task ReadOnlySpan_ContainsAnyExcept_NullElements()
+    {
+        ReadOnlySpan<string?> span = new string?[] { null, "a", "b" };
+        var one = span.ContainsAnyExcept((string?)null);
+        var two = span.ContainsAnyExcept(null, "a");
+        var three = span.ContainsAnyExcept(null, "a", "b");
+        var many = span.ContainsAnyExcept(new string?[] { "a", null });
+        var none = span.ContainsAnyExcept(new string?[] { "a", null, "b" });
+        ReadOnlySpan<string?> nulls = new string?[] { null, null };
+        var onlyNulls = nulls.ContainsAnyExcept((string?)null);
+        var nullsExceptA = nulls.ContainsAnyExcept("a");
+        await Assert.That(one).IsTrue();
+        await Assert.That(two).IsTrue();
+        await Assert.That(three).IsFalse();
+        await Assert.That(many).IsTrue();
+        await Assert.That(none).IsFalse();
+        await Assert.That(onlyNulls).IsFalse();
+        await Assert.That(nullsExceptA).IsTrue();
+    }
+
+    [Test]
+    public async Task Span_ContainsAnyExcept_NullElements()
+    {
+        Span<string?> span = new string?[] { null, "a", "b" };
+        var one = span.ContainsAnyExcept((string?)null);
+        var two = span.ContainsAnyExcept(null, "a");
+        var three = span.ContainsAnyExcept(null, "a", "b");
+        var many = span.ContainsAnyExcept(new string?[] { "a", null });
+        var none = span.ContainsAnyExcept(new string?[] { "a", null, "b" });
+        Span<string?> nulls = new string?[] { null, null };
+        var onlyNulls = nulls.ContainsAnyExcept((string?)null);
+        var nullsExceptA = nulls.ContainsAnyExcept("a");
+        await Assert.That(one).IsTrue();
+        await Assert.That(two).IsTrue();
+        await Assert.That(three).IsFalse();
+        await Assert.That(many).IsTrue();
+        await Assert.That(none).IsFalse();
+        await Assert.That(onlyNulls).IsFalse();
+        await Assert.That(nullsExceptA).IsTrue();
+    }
 }
diff --git a/src/Tests/PolyfillTests_Memory_IndexOfAnyExcept.cs b/src/Tests/PolyfillTests_Memory_IndexOfAnyExcept.cs
index f577e3de..b93e09f7 100644
--- a/src/Tests/PolyfillTests_Memory_IndexOfAnyExcept.cs
+++ b/src/Tests/PolyfillTests_Memory_IndexOfAnyExcept.cs
@@ -89,4 +89,40 @@ public async Task Span_IndexOfAnyExcept_SingleValue_NotFound()
         var result = span.IndexOfAnyExcept(1);
         await Assert.That(result).IsEqualTo(-1);
     }
+
+    [Test]
+    public async Task ReadOnlySpan_IndexOfAnyExcept_NullElements()
+    {
+        ReadOnlySpan<string?> span = new string?[] { null, "a", "b", "c" };
+        var one = span.IndexOfAnyExcept((string?)null);
+        var two = span.IndexOfAnyExcept(null, "a");
+        var three = span.IndexOfAnyExcept(null, "a", "b");
+        var many = span.IndexOfAnyExcept(new string?[] { "a", null });
+        var none = span.IndexOfAnyExcept(new string?[] { "a", null, "b", "c" });
+        var exceptC = span.IndexOfAnyExcept("c");
+        await Assert.That(one).IsEqualTo(1);
+        await Assert.That(two).IsEqualTo(2);
+        await Assert.That(three).IsEqualTo(3);
+        await Assert.That(many).IsEqualTo(2);
+        await Assert.That(none).IsEqualTo(-1);
+        await Assert.That(exceptC).IsEqualTo(0);
+    }
+
+    [Test]
+    public async Task Span_IndexOfAnyExcept_NullElements()
+    {
+        Span<string?> span = new string?[] { null, "a", "b", "c" };
+        var one = span.IndexOfAnyExcept((string?)null);
+        var two = span.IndexOfAnyExcept(null, "a");
+        var three = span.IndexOfAnyExcept(null, "a", "b");
+        var many = span.IndexOfAnyExcept(new string?[] { "a", null });
+        var none = span.IndexOfAnyExcept(new string?[] { "a", null, "b", "c" });
+        var exceptC = span.IndexOfAnyExcept("c");
+        await Assert.That(one).IsEqualTo(1);
+        await Assert.That(two).IsEqualTo(2);
+        await Assert.That(three).IsEqualTo(3);
+        await Assert.That(many).IsEqualTo(2);
+        await Assert.That(none).IsEqualTo(-1);
+        await Assert.That(exceptC).IsEqualTo(0);
+    }
 }
diff --git a/src/Tests/PolyfillTests_Memory_LastIndexOfAnyExcept.cs b/src/Tests/PolyfillTests_Memory_LastIndexOfAnyExcept.cs
index 2f79747d..f85c3907 100644
--- a/src/Tests/PolyfillTests_Memory_LastIndexOfAnyExcept.cs
+++ b/src/Tests/PolyfillTests_Memory_LastIndexOfAnyExcept.cs
@@ -89,4 +89,40 @@ public async Task Span_LastIndexOfAnyExcept_SingleValue_NotFound()
         var result = span.LastIndexOfAnyExcept(1);
         await Assert.That(result).IsEqualTo(-1);
     }
+
+    [Test]
+    public async Task ReadOnlySpan_LastIndexOfAnyExcept_NullElements()
+    {
+        ReadOnlySpan<string?> span = new string?[] { null, "a", "b", "c" };
+        var one = span.LastIndexOfAnyExcept((string?)null);
+        var two = span.LastIndexOfAnyExcept(null, "a");
+        var three = span.LastIndexOfAnyExcept(null, "a", "b");
+        var many = span.LastIndexOfAnyExcept(new string?[] { "a", null });
+        var none = span.LastIndexOfAnyExcept(new string?[] { "a", null, "b", "c" });
+        var exceptC = span.LastIndexOfAnyExcept("c");
+        await Assert.That(one).IsEqualTo(3);
+        await Assert.That(two).IsEqualTo(3);
+        await Assert.That(three).IsEqualTo(3);
+        await Assert.That(many).IsEqualTo(3);
+        await Assert.That(none).IsEqualTo(-1);
+        await Assert.That(exceptC).IsEqualTo(2);
+    }
+
+    [Test]
+    public async Task Span_LastIndexOfAnyExcept_NullElements()
+    {
+        Span<string?> span = new string?[] { null, "a", "b", "c" };
+        var one = span.LastIndexOfAnyExcept((string?)null);
+        var two = span.LastIndexOfAnyExcept(null, "a");
+        var three = span.LastIndexOfAnyExcept(null, "a", "b");
+        var many = span.LastIndexOfAnyExcept(new string?[] { "a", null });
+        var none = span.LastIndexOfAnyExcept(new string?[] { "a", null, "b", "c" });
+        var exceptC = span.LastIndexOfAnyExcept("c");
+        await Assert.That(one).IsEqualTo(3);
+        await Assert.That(two).IsEqualTo(3);
+        await Assert.That(three).IsEqualTo(3);
+        await Assert.That(many).IsEqualTo(3);
+        await Assert.That(none).IsEqualTo(-1);
+        await Assert.That(exceptC).IsEqualTo(2);
+    }
 }

From 6da5513e92fa989fba56aca8dfe930597b27e921 Mon Sep 17 00:00:00 2001
From: GitHub Action <action@github.com>
Date: Sun, 11 Oct 2026 12:19:10 +0000
Subject: [PATCH 2/2] Docs changes

---
 readme.md | 48 ++++++++++++++++++++++++------------------------
 1 file changed, 24 insertions(+), 24 deletions(-)

diff --git a/readme.md b/readme.md
index 0e206798..13dd7d23 100644
--- a/readme.md
+++ b/readme.md
@@ -1768,10 +1768,10 @@ The class `Polyfill` includes the following extension methods:
  * `int CommonPrefixLength<T>(ReadOnlySpan<T>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.commonprefixlength?view=net-11.0#system-memoryextensions-commonprefixlength-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
  * `bool Contains<T>(T, IEqualityComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.contains?view=net-11.0#system-memoryextensions-contains-1(system-readonlyspan((-0))-0-system-collections-generic-iequalitycomparer((-0))))
  * `bool Contains<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.contains?view=net-11.0#system-memoryextensions-contains-1(system-readonlyspan((-0))-0))
- * `bool ContainsAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
- * `bool ContainsAnyExcept<T>(T, T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0-0-0))
- * `bool ContainsAnyExcept<T>(T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0-0))
- * `bool ContainsAnyExcept<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0))
+ * `bool ContainsAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
+ * `bool ContainsAnyExcept<T>(T, T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0-0-0))
+ * `bool ContainsAnyExcept<T>(T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0-0))
+ * `bool ContainsAnyExcept<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-readonlyspan((-0))-0))
  * `bool ContainsAnyExceptInRange<T>(T, T) where T : IComparable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexceptinrange?view=net-11.0#system-memoryextensions-containsanyexceptinrange-1(system-readonlyspan((-0))-0-0))
  * `bool ContainsAnyInRange<T>(T, T) where T : IComparable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyinrange?view=net-11.0#system-memoryextensions-containsanyinrange-1(system-readonlyspan((-0))-0-0))
  * `int CountAny<T>(ReadOnlySpan<T>, IEqualityComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.countany?view=net-11.0#system-memoryextensions-countany-1(system-readonlyspan((-0))-system-readonlyspan((-0))-system-collections-generic-iequalitycomparer((-0))))
@@ -1780,14 +1780,14 @@ The class `Polyfill` includes the following extension methods:
  * `bool EndsWith<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.endswith?view=net-11.0#system-memoryextensions-endswith-1(system-readonlyspan((-0))-0))
  * `int IndexOf<T>(T, IEqualityComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexof?view=net-11.0#system-memoryextensions-indexof-1(system-readonlyspan((-0))-0-system-collections-generic-iequalitycomparer((-0))))
  * `int IndexOfAny<T>(ReadOnlySpan<T>, IEqualityComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.countany?view=net-11.0#system-memoryextensions-countany-1(system-readonlyspan((-0))-system-buffers-searchvalues((-0))))
- * `int IndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
- * `int IndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0-0-0))
- * `int IndexOfAnyExcept<T>(T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0-0))
- * `int IndexOfAnyExcept<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0))
- * `int LastIndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
- * `int LastIndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0-0-0))
- * `int LastIndexOfAnyExcept<T>(T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0-0))
- * `int LastIndexOfAnyExcept<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0))
+ * `int IndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
+ * `int IndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0-0-0))
+ * `int IndexOfAnyExcept<T>(T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0-0))
+ * `int IndexOfAnyExcept<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-readonlyspan((-0))-0))
+ * `int LastIndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-system-readonlyspan((-0))))
+ * `int LastIndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0-0-0))
+ * `int LastIndexOfAnyExcept<T>(T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0-0))
+ * `int LastIndexOfAnyExcept<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-readonlyspan((-0))-0))
  * `T? Max<T>(IComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.max?view=net-11.0#system-memoryextensions-max-1(system-readonlyspan((-0))-system-collections-generic-icomparer((-0))))
  * `T? Max<T>()` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.max?view=net-11.0#system-memoryextensions-max-1(system-readonlyspan((-0))))
  * `T? Min<T>(IComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.min?view=net-11.0#system-memoryextensions-min-1(system-readonlyspan((-0))-system-collections-generic-icomparer((-0))))
@@ -1946,20 +1946,20 @@ The class `Polyfill` includes the following extension methods:
  * `int CommonPrefixLength<T>(ReadOnlySpan<T>, IEqualityComparer<T>?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.commonprefixlength?view=net-11.0#system-memoryextensions-commonprefixlength-1(system-span((-0))-system-readonlyspan((-0))-system-collections-generic-iequalitycomparer((-0))))
  * `int CommonPrefixLength<T>(ReadOnlySpan<T>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.commonprefixlength?view=net-11.0#system-memoryextensions-commonprefixlength-1(system-span((-0))-system-readonlyspan((-0))))
  * `bool Contains<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.contains?view=net-11.0#system-memoryextensions-contains-1(system-span((-0))-0))
- * `bool ContainsAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-system-readonlyspan((-0))))
- * `bool ContainsAnyExcept<T>(T, T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0-0-0))
- * `bool ContainsAnyExcept<T>(T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0-0))
- * `bool ContainsAnyExcept<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0))
+ * `bool ContainsAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-system-readonlyspan((-0))))
+ * `bool ContainsAnyExcept<T>(T, T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0-0-0))
+ * `bool ContainsAnyExcept<T>(T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0-0))
+ * `bool ContainsAnyExcept<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexcept?view=net-11.0#system-memoryextensions-containsanyexcept-1(system-span((-0))-0))
  * `bool ContainsAnyExceptInRange<T>(T, T) where T : IComparable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyexceptinrange?view=net-11.0#system-memoryextensions-containsanyexceptinrange-1(system-span((-0))-0-0))
  * `bool ContainsAnyInRange<T>(T, T) where T : IComparable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.containsanyinrange?view=net-11.0#system-memoryextensions-containsanyinrange-1(system-span((-0))-0-0))
- * `int IndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-system-readonlyspan((-0))))
- * `int IndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0-0-0))
- * `int IndexOfAnyExcept<T>(T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0-0))
- * `int IndexOfAnyExcept<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0))
- * `int LastIndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-system-readonlyspan((-0))))
- * `int LastIndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0-0-0))
- * `int LastIndexOfAnyExcept<T>(T, T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0-0))
- * `int LastIndexOfAnyExcept<T>(T) where T : IEquatable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0))
+ * `int IndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-system-readonlyspan((-0))))
+ * `int IndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0-0-0))
+ * `int IndexOfAnyExcept<T>(T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0-0))
+ * `int IndexOfAnyExcept<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.indexofanyexcept?view=net-11.0#system-memoryextensions-indexofanyexcept-1(system-span((-0))-0))
+ * `int LastIndexOfAnyExcept<T>(ReadOnlySpan<T>) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-system-readonlyspan((-0))))
+ * `int LastIndexOfAnyExcept<T>(T, T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0-0-0))
+ * `int LastIndexOfAnyExcept<T>(T, T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0-0))
+ * `int LastIndexOfAnyExcept<T>(T) where T : IEquatable<T>?` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.lastindexofanyexcept?view=net-11.0#system-memoryextensions-lastindexofanyexcept-1(system-span((-0))-0))
  * `void Sort<T>(Comparison<T>)`
  * `void Sort<T>() where T : IComparable<T>` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.memoryextensions.sort?view=net-11.0#system-memoryextensions-sort-1(system-span((-0))))