Re: [PHP-DEV] [Discussion] Revisiting typed closures

Totally with you on not special-casing closures. A general alias feature is
the right long-term home. But I'd push back on waiting for it before
settling the inline syntax, because the two aren't really alternatives.

I'm no expert in the topic, but I guess an alias needs something to alias.
use type callable(int): string as Foo; probably only works once
callable(int): string is a valid type on its own or something like that. I
mean supporting the inline syntax doesn't sound like conflicting /
additional work that type alias could avoid.

If that's correct, the inline grammar is the primitive; aliases are just a
naming layer on top, and we would need inline either way.

I just found that C# is a nice warning signal here: it started
reference-only (you had to declare a named delegate per signature), found
that painful enough that Func/Action were added precisely so you don't have
to declare a delegate to spell a function type.

See https://learn.microsoft.com/en-us/dotnet/api/system.func-2?view=net-10.0

Even the reference-only poster child ended up needing a declaration-free
way to write these inline.

Last but not least, the type-aliases RFC is still under discussion, with
callable signatures sitting in future scope.

Does it makes sense to wait for something that isn't a blocker nor an
enabler?