Typed Template Haskell sneakily allows impredicativity
The following module is accepted:
{-# LANGUAGE ExplicitForAll, TemplateHaskell #-}
module Bug where
impred :: forall a. a -> a
impred = $$( [|| \x -> x ||] )But that requires an intermediate TExp (forall a. a -> a).
Will fix in ongoing work.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 8.1 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |
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