See rust-lang/rust#99447 (comment)
The fact that $crate in the macro_rules LHS is accepted and glued into kw::DollarCrate is likely an accidental bug. The single use is an internal macro helper arm,
| (@parse ::core::marker::PhantomData::<$crate::Ix0>,::core::marker::PhantomData::<$crate::Ix0>,[]) => { |
which looking at the macro, should probably be written to take $in_dim:expr, $out_dim:expr, like the other arms anyway.
See rust-lang/rust#99447 (comment)
The fact that
$cratein the macro_rules LHS is accepted and glued intokw::DollarCrateis likely an accidental bug. The single use is an internal macro helper arm,ndarray/src/slice.rs
Line 845 in f8522cf
which looking at the macro, should probably be written to take
$in_dim:expr, $out_dim:expr,like the other arms anyway.