Wraparound +% not for literals?

[PavelVozenilek]

I try this in online tool:

const std = @import("std");
const warn = std.debug.warn;

pub fn main() void {

  const o : u8 = 200 +% 200;
  warn("{}\n", o);    
}

and it gives me error:

/home/runner/.code.tio:6:22: error: integer value 400 cannot be implicitly casted to type 'u8'

I expected wraparounds to work at compile time too.

[andrewrk]

comptime integers never wrap. They have unlimited bits. You need to cast your literals to a specific number of bits before doing a wraparound operation.

[PavelVozenilek]

Contrary to previous example, where intent was clear, this compiles:

pub fn main() void {

  const o = 200 +% 200;
}

IMHO it should not. It is not clear what the programmer wanted.

[PavelVozenilek]

@andrewrk

This compiles and produces correct result:

const std = @import("std");
const warn = std.debug.warn;

pub fn main() void {

  const o : u8 = u8(200) +% u8(200);
  warn("{}\n", o);    
}

But it feels as superfluous, to cast everything when there is no ambiguity.