Re: Proposal: Remove Semigroup and Monoid instances for Data.Map, Data.IntMap, Data.HashMap

On Tue, 13 Feb 2018, David Feuer wrote:

1. Deprecate the Semigroup and Monoid instances for Data.Map.Map, Data.IntMap.IntMap, and Data.HashMap.HashMap in the next releases of containers and unordered-containers.

2. Remove the deprecated instances.

3. After another several years (four or five, perhaps?), make a major release of each package in which the instances are replaced with the following:

I like the plan. Re-adding with Semigroup superclass would prevent silent re-interpretation of code if it is generic.