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Failure to resolve AnyK

Consider the following code:

{-# LANGUAGE PolyKinds,
             GADTs,
             DataKinds,
             KindSignatures
 #-}

data SList a where
  SNil :: SList '[]

x :: SList ('[] :: [Bool])
x = SNil

Compiling this code causes GHC to emit an error saying that AnyK cannot be unified with Bool. It seems that AnyK is a placeholder for an undetermined kind and that it should unify with any well-formed kind.

As a much smaller issue, the error emitted speaks about "types" where it means "kinds".

Trac metadata
Trac field Value
Version 7.4.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler (Type checker)
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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