Henning Thielemann
#if HUGS import Hugs.Base #elseif GHC import GHC.Base #endif
We just need a system for plugging together system-dependent modules, that's all. We do not need preprocessor hacks for this issue: http://www.haskell.org/pipermail/haskell-cafe/2006-August/017503.html
But in general, I often find I want to use CPP both to modify imports and provide function definitions. E.g. to provide sensible error messages for some Prelude functions (read, head, fromJust, etc), I have an include file that imports Prelude hiding the original definitions, and replace them with macros making use of CPP's __LINE__ and __FILE__. For some of the support functionality, I'm forced to write macros instead of functions, since I'd otherwise need to clutter all my modules with multiple #include statements. This tends to arise relatively often when I use #include -- if it is simple to implement, could perhaps this (mixing of imports and definitions) be allowed when -cpp is specified? -k -- If I haven't seen further, it is by standing in the footprints of giants