Ideally, tt matches either a single token or delimited sequence (e.g. { arbitrary tokens }).
However, the following compiles today:
macro_rules! m { ($t:tt) => {} }
m!($x);
m!($(x)*);
m!($x:ident);
We want to avoid leaking details of macro_rules! syntax into the semantics of tt, at least for macros 2.0.
Ideally,
ttmatches either a single token or delimited sequence (e.g.{ arbitrary tokens }).However, the following compiles today:
We want to avoid leaking details of
macro_rules!syntax into the semantics oftt, at least for macros 2.0.