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 |