macro_rules! impl_typed_slice_conversions {
($type:ty, $error:ident, $desc:expr) => { ... };
($type:ty, $vec_error:ident, $slice_error:ident, $mut_error:ident, $desc:expr) => { ... };
}macro_rules! impl_typed_slice_conversions {
($type:ty, $error:ident, $desc:expr) => { ... };
($type:ty, $vec_error:ident, $slice_error:ident, $mut_error:ident, $desc:expr) => { ... };
}