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

Malcolm Wallace malcolm.wallace at
Sun Aug 14 16:50:38 CEST 2011

On 14 Aug 2011, at 15:25, Yitzchak Gale wrote:

> Thomas Schilling wrote:
>> My argument would be that since Monoid is used more commonly,
>> it should get the nice and short name (<>).
> If it is defined in Data.Semigroup, then it can be used for
> both.

I am in favour of <> for Monoid mappend, indeed I thought this had already been decided a long time ago.

I oppose any dependency (at this stage) on Semigroup.  For one thing, I don't know what a semigroup is.  There is next to no Haddock documentation for the semigroup package, so I am not further enlightened by looking there.  As a consequence, I have no idea how to make my types which are currently Monoids into SemiGroups.  For instance, although I can guess at "sconcat", what semantics is "replicate1p" supposed to have?  What algebraic laws am I supposed to be respecting?


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