typedef with generic types requires type arguments

[mihaibudiu]

Signed-off-by: Mihai Budiu [email protected]

Fixes #3170

[mihaibudiu]

Fixes #3172
... by just forbidding the example.

[apinski-cavium]

Is this even invalid because the specification is not clear here.

[apinski-cavium]

Actually I think it should be invalid, though the specifications should be clear too.

[jnfoster]

I agree this was a compiler bug. Can you point out where the spec is unclear? In the example program that illustrated the bug, I'd argue a generic without its type arguments isn't really a type.

[mihaibudiu]

That generic is something like a function that takes some type arguments and returns a type. Not really a type, indeed.
I think that both behaviors are reasonable (the previous one, and the current one), but since no one asked for this feature I think it's safe to not allow it.

[mihaibudiu]

So, can anyone approve this PR?

[jnfoster]

My pleasure.