Proposal #3999: Improved folds for Data.Map and Data.IntMap

Roman Leshchinskiy rl at
Mon Apr 26 23:26:16 EDT 2010

On 27/04/2010, at 03:20, Louis Wasserman wrote:

> I'm not sure why you don't just use curry directly here. Also, why not just implement toAscList like in the rule and INLINE it?
> I concede that using curry directly is the better approach, but when I implement toAscList as in the rule and inline it, it doesn't actually appear to get inlined.  (Example: mapKeysWith, which is defined as fromListWith c . fFirst . toList, doesn't actually fold/build with the map.)

Is this with 6.12 or the HEAD? In any case, could you please submit a bug report so that Simon can have a look at it.


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