warn about language extensions that are not used
When I put
{-# OPTIONS_GHC -Wall -Werror #-}
in my source file, I don't get compiler warnings about redundant language extensions that I enabled in that file.
For example if I write
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
in the file, but I never do newtype deriving, the compiler could give me a warning.
It would be nice if the compiler gave warnings about this, since after refactoring, some language extensions might not be needed anymore, and hence should be removed since fewer language extensions mean more stable and portable code no?
Trac metadata
| Trac field | Value |
|---|---|
| Version | 6.10.1 |
| Type | FeatureRequest |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |