Warning about module abbreviation clashes
|Reported by:||Lemming||Owned by:|
|Type of failure:||Incorrect warning at compile-time||Test Case:|
|Related Tickets:||Differential Rev(s):|
Please add the option -fwarn-module-rename-collision that makes GHC to do the following: If GHC encounters an import situation like
module Main where import qualified Data.A as A import qualified Control.A as A
then GHC should emit a warning like
Main.hs:3:0: Main.hs:4:0: Warning: Both Data.A and Control.A are renamed to A. An identifier like A.ident can only be resolved, if it is either in Data.A or Control.A. Better rename both modules to different names.
Reason for this warning is, that if 'ident' is from Data.A as of writing Main, and later another variable named 'ident' is added to Control.A, then A.ident can no longer be resolved in Main. That is, by accidental module rename collisions even qualified imports carry the risk of future name collisions.
Related to #4977
Change History (12)
comment:6 Changed 4 years ago by igloo
- Milestone changed from 7.4.1 to 7.6.1
- Priority changed from normal to low
comment:11 Changed 6 months ago by thomie
- Type of failure changed from None/Unknown to Incorrect warning at compile-time