Proposal: more general unionWith for Data.Map

Johan Tibell johan.tibell at
Tue Jan 24 20:52:23 CET 2012

On Tue, Jan 24, 2012 at 11:42 AM, Christian Sattler
<sattler.christian at> wrote:
> I don't care much about the naming, but note that the analogous
> property already fails for the generalized intersectionWithKey in the
> development version.

I suspected as much. I think the current intersectionWithKey is
broken. We should have a single function, mergeWithKey, that allows
people to do the things they currently do using Maybe return values in
e.g. intersectionWithKey.


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