Adding an ignore function to Control.Monad

Felipe Lessa felipe.lessa at
Thu Jun 11 16:26:45 EDT 2009

On Thu, Jun 11, 2009 at 04:14:22PM -0400, David Menendez wrote:
> Aside from assertions that this is a bad thing because you say so,
> what evidence do we have that this is a problem?

The wiki mentions the problem with forgetting the results of an
operation.  Another problem is using functions that needlessly
produce results because you're interested in the side effects
only.  For example,

  do mapM something1 list

(Hmmm, would something like

  {-# RULES "mapM/mapM_" mapM = mapM_ #-}

work nicely?)


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