Remove anytype?

[novel mica]

I found out that zig doesnt take language proposals on github anymore so i'm posting this here because i wonder what people think :D

Random idea: replace anytype with functions that imperatively check for type conformance?

instead of

fn foo(sink: anytype) void { ... }

it would be

fn foo(sink: isWriter) void { ... }

where

fn isWriter(comptime t: type) void {
  if (!std.meta.hasFn("write")(t)) @compileErorr(...);
}

I dont think it makes currently sense to use a function name in place of function argument?

[red crane]

i guess you could always bring it back with this lol
fn anytype(comptime T: type) void {}

from what i know though andrew isnt too big a fan of type checking on anytypes and just wants the duck typing system to do that for you

what would be nice (imo) is if in the error trace for an incorrect type on an anytype paramter, it included the user's call site (not just as a line number, but the actual call site and point to the argument that was of the wrong type)

[novel mica]

yeah the compile errors from the checking function could totally be attached to the call site argument. I think it would look really nice

the thing about anytype duck typing is that the error can occur outside of your code and it says something like 'x has no y' where x is some random local variable.