C preprocessor + WinHugs

[Malcolm Wallace]

Neil Mitchell <ndmitchell at gmail.com> writes:

> > None are terribly attractive (and they would only be for cpp).
> >
> I agree. Is there no other way to stop the preprocessor running on all
> files, and restricting it to just those which are needed?

There was talk at one stage of a standard language-extensions pragma,
corresponding to your third option.
    {-# LANGUAGE cpp MPTC fundeps #-}
I think SimonM has just implemented it for ghc, the rest of us are
lagging behind.

FWIW, hmake uses both of your first two suggestions - detect a # in the
first column, and also permit a filename extension to trigger cpp.  The
latter doesn't seem too awful, since other preprocessors use the same
method (Happy .y, Alex .x, hsc2hs .hsc, etc).

Regards,
    Malcolm