On Tue, Oct 14, 2008 at 1:45 PM, J. Garrett Morris
<jgmorris at cecs.pdx.edu> wrote:
> mapM and mapM_ have different complexity - I don't know if the
> compiler would be smart enough to infer mapM_ style behavior for (void
> . mapM).
But there's the possibility of {-# RULES #-} pragmas to help it be smart enough.
Luke