Improved slice documentation

[spencer3035]

Improve slice documentation to include assert_eq checks for all the cases where there were existing examples. I think it makes things more clear when the documentation explicitly checks against values and shows the reader what it does.

I also started a rust internals discussion about it here: https://internals.rust-lang.org/t/improve-slice-documentaion/21168

[rustbot]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @joboet (or someone else) some time within the next two weeks.

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[jhpratt]

@bors r+ rollup

[bors]

📌 Commit c49a530 has been approved by jhpratt

It is now in the queue for this repository.

[jhpratt]

@bors r-

Failing CI. Let me know when it's fixed (please keep it as a single commit) and I'll re-approve.

@rustbot claim

[spencer3035]

Classic off by one error. Should be fixed now. @jhpratt

[jhpratt]

Can you squash it into one commit?

[spencer3035]

I force pushed the two commits into one commit.

[jhpratt]

Thanks!

@bors r+

[bors]

📌 Commit 163d98b has been approved by jhpratt

It is now in the queue for this repository.