Julia: TypeVars in tuples in type parameters

[iamed2]

julia> type Foo{N} end

julia> Foo{(true, true)}
Foo{(true,true)}

julia> typealias Bar{N} Foo{N}
Foo{N}

julia> Bar{(true, true)}
Foo{(true,true)}

julia> typealias Baz Foo{(true, true)}
Foo{(true,true)}

julia> typealias Quuz{M, N} Foo{(M, N)}
TypeError: Foo: in parameter, expected Type{T}, got Tuple{TypeVar,TypeVar}

Yes, those are supposed to be tuples and not tuple types. I blame @Keno (https://github.com/Keno/Cxx.jl/blob/master/src/cxxtypes.jl#L52).

I fully expect this to be unsupported, but I hope that gets @Keno to change (true, false, false) to Tuple{Val{true}, Val{false}, Val{false}} in Cxx.jl.

[Keno]

In my defense those used to be one and the same.

[iamed2]

That's legit. I'm also digging into Cxx implementation details in order to dispatch on Cxx types, which maybe you hoped people wouldn't do.

[JeffBezanson]

Tuple{true, false, false} also works (although slightly weird since it can't actually be the type of anything).

Closing as wontfix, since I don't think we're planning to be able to quantify over tuples.