Indeed, being able to introduce a short name for the current module, or having a fixed short name like 'This' or 'Self' would be neat. The standard workaround for your example would be import Prelude hiding (length,null) Did you try a .hs-boot file with your self-import trick? Cheers, Andreas On 29.09.2014 10:19, Herbert Valerio Riedel wrote:
Hello *,
Here's a situation I've encountered recently, which mades me wish to be able to define a local alias (in order to avoid CPP use). Consider the following stupid module:
module AnnoyinglyLongModuleName ( AnnoyinglyLongModuleName.length , AnnoyinglyLongModuleName.null ) where
length :: a -> Int length _ = 0
null :: a -> Bool null = (== 0) . AnnoyinglyLongModuleName.length
Now it'd be great if I could do the following instead:
module AnnoyinglyLongModuleName (M.length, M.null) where
import AnnoyinglyLongModuleName as M -- <- does not work
length :: a -> Int length _ = 0
null :: a -> Bool null = (== 0) . M.length
However, if I try to compile this, GHC complains about
AnnoyinglyLongModuleName.hs:4:1: Bad interface file: AnnoyinglyLongModuleName.hi AnnoyinglyLongModuleName.hi: openBinaryFile: does not exist (No such file or directory)
while GHCi tells me:
Module imports form a cycle: module ‘AnnoyinglyLongModuleName’ (AnnoyinglyLongModuleName.hs) imports itself
Is there some other way (without CPP) to create a local alias for the current module-name? If not, is there a reason GHC couldn't support this special case of self-aliasing the current module name?
PS: Alternatively, this could be done as a language extension but that'd require extending the Haskell grammar:
module AnnoyinglyLongModuleName as M (M.length, M.null) where
Cheers, hvr _______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://www.haskell.org/mailman/listinfo/ghc-devs
-- Andreas Abel <>< Du bist der geliebte Mensch. Department of Computer Science and Engineering Chalmers and Gothenburg University, Sweden andreas.abel@gu.se http://www2.tcs.ifi.lmu.de/~abel/