ability to obtain return type of generic function when it has no dependencies

[Hejsil]

test "" {
    var t: @typeOf(@import("std").fmt.parseInt).ReturnType = undefined;
}

zsh: segmentation fault (core dumped)  zig test test.zig

[andrewrk]

I believe this is related to parseInt being a generic function

[Hejsil]

Oooh ye, that might be it. Tried a few other functions like allocPrint, but ofc, that is also generic.

Here is the bare bones version:

fn a(b: var) void {}

test "" {
    var c : @typeOf(a).ReturnType = undefined;
}

[Hejsil]

@andrewrk Do we mark this as fixed? The compiler doesn't crash on anymore and gives an error message instead.

The real question, if my bare bones example should work or not. After all, void is known, even if b is generic. The compiler just doesn't analyze past b. It's probably a complicated thing to make work, so maybe not.

[andrewrk]

The real question, if my bare bones example should work or not.

I'm not sure. It's a difficult question that I'm not prepared to address yet. Let's revisit closer to 1.0.0.

[andrewrk]

Possibly related to #2174, but I'm not sure.

[FireFox317]

This would also allow for the proper return types to show up in the generated documentation.

[mitchellh]

I think this is resolved in stage2: #11188

If the return type isn't dependent on generic parameters, it returns the type.

[andrewrk]

That's correct. The only thing missing to close this issue is to add a behavior test.

[Vexu]

A test for this already exists in test/behavior/type_info.zig:

zig/test/behavior/type_info.zig

Line 378 in b40fc70

test "type info: generic function types" {