Kind variable problem when declaring associated type family
The following code fails to compile:
{-# LANGUAGE PolyKinds, TypeFamilies #-}
class Foo a where
type Bar a
type Bar a = IntThe error I get is
Type indexes must match class instance head
Found `k' but expected `k'
In the type synonym instance default declaration for `Bar'
In the class declaration for `Foo'When I remove -XPolyKinds, the code compiles without a hiccup.
This was tested on 7.5.2012.0710
Trac metadata
| Trac field | Value |
|---|---|
| Version | 7.5 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler (Type checker) |
| Test case | |
| Differential revisions | |
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| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |