class ??? with Haddock

[Sven Panne]

Wolfgang Jeltsch wrote:
> does Hugs understand C preprocessor macros?  If not, your approach would be 
> bad for me since I try to stay Hugs-compatible.

Well, Hugs itself doesn't understand CPP macros (neither does GHC), but you
can use Hugs' -F<cmd> flag to pipe the source files through <cmd> before
Hugs actually sees them. GHC has two related options, -pgmP <cmd> and -cpp.

FYI: The hierarchical libraries are full of CPP stuff to handle the differences
between various platforms and/or Haskell system, but the Hugs distributions
usually come with preprocessed versions, so you don't necessarily need cpp.

Cheers,
    S.