On Saturday, 9 June 2018 at 02:13:00 UTC, Walter Bright wrote:
'in' is supposed to mean 'scope const'. But it was never
enforced, meaning that suddenly enforcing it is just going to
break code left and right.
I think the breakage would be simple to mitigate. Anywhere `in`
is used we display a deprecation message...
"Deprecation: `in` is currently equivalent to `const`. In
v2.{whatever} `in` will be changed to `scope const`. To keep the
current semantics, replace `in` with `const`. To silence this
message change your code to `scope const` or simply ignore this
message until v2.{whatever}. See
https://dlang.org/spec/function.html#parameters for more
information.
... and update the documentation to explain the change.
Simple! And when v2.{whatever} comes around, we're all set with a
better D.
Mike
