[Haskell-cafe] extension to filter with external program (was: Current status of Mavericks CPP)

[Tobias Florek]

hi,

i may certainly be missing something, as i only used cpp in haskell for 
conditional compilation. having said that:

i'd like to have (instead of LANGUAGE CPP) the following extension.

LANGUAGE FilterWithExternalProgram my_cpp

that would make it possible to use a cpp implementation implemented 
separately from ghc and would leave it to the ecosystem to implement 
best practices (i.e. a haskell implementation of cpp or the proposed 
declarative extension).

i _guess_ that should also make it easier to use compile-to-haskell 
programs like she. maybe a hypothetical template haskell alternative 
might also work with it.

regards,
  tobias florek