GHC.TypeLits import don't quite work
If you explicitly import any of the things that are Compiler Magic from GHC.TypeLits
you get an error:
import GHC.TypeLits ((+), (-))
...
[1 of 1] Compiling Main ( typelit_export_bug.hs, interpreted )
typelit_export_bug.hs:1:22:
Module `GHC.TypeLits' does not export `(+)'
typelit_export_bug.hs:1:27:
Module `GHC.TypeLits' does not export `(-)'
Failed, modules loaded: none.
If you do the opposite, it also doesn't work
import GHC.TypeLits hiding ((+), (-))
...
[1 of 1] Compiling Main ( typelit_export_bug.hs, interpreted )
typelit_export_bug.hs:3:1: Warning:
Module `GHC.TypeLits' does not export `(+)'
typelit_export_bug.hs:3:1: Warning:
Module `GHC.TypeLits' does not export `(-)'
The use case is that I would like to define my own +
and have one instance for Nat
and others for other types of my choosing. It isn't more than a minor annoyance, however, there aren't many thing defined in GHC.TypeLits
so I can write import qualified GHC.TypeLits; import GHC.TypeLits (Nat, natVal, Symbol, symbolVal ...
Trac metadata
Trac field | Value |
---|---|
Version | 7.8.2 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |