Standalone deriving Generic on type with instantiated arguments
Reiner Pope reports that the following code
{-# LANGUAGE DeriveGeneric, FlexibleInstances, StandaloneDeriving #-}
import GHC.Generics
data T a = T a
deriving instance Generic (T Bool)
generates the following:
instance Generic (T Bool) where ...
type instance Rep (T a) = ...
This is wrong. The type instance should probably be for Rep (T Bool)
. Or perhaps we should refuse to derive Generic for instantiated types altogether.
Trac metadata
Trac field | Value |
---|---|
Version | 7.4.1 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | reiner.pope@gmail.com |
Operating system | |
Architecture |