Proposal #3339: Add (+>) as a synonym for mappend

Thomas Schilling nominolo at
Sun Aug 14 16:08:20 CEST 2011

On 14 August 2011 14:53, Yitzchak Gale <gale at> wrote:
> Thomas Schilling wrote:
>> So, NOTHING would break if you made made SemiGroup a superclass of Monoid?
> Right, I didn't propose that. Really, in hindsight, it should be. But
> as you say,
> it would break things. Sorry if I was not clear.
> Rather, each library author should add the superclass.
> Unfortunately, this is similar to the situation with Functor and
> Monad.

Right.  My argument would be that since Monoid is used more commonly,
it should get the nice and short name (<>).  Of course, SemiGroup as a
superclass of Monoid would be nicer.

I wonder, how hard it would be to provide an automatic rewriting tool
that would rewrite your source code.  (This tool would use the GHC

Push the envelope. Watch it bend.

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