A more useful Monoid instance for Data.Map

Ben Gamari bgamari.foss at gmail.com
Tue Mar 12 16:08:51 CET 2013

Roman Cheplyaka <roma at ro-che.info> writes:

> So maybe we should push the change that was discussed in another thread
> to move Semigroup into base, and only then change this instance.
Are you proposing that (.++.) /= mappend?

I think this sort of inconsistency would be a mistake, especially given
the evidence that suggests that relatively little code will be affected
by the change in mappend's semantics.


- Ben

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