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

Yitzchak Gale gale at
Sun Aug 14 15:43:41 CEST 2011

Johan Tibell wrote:
>> This is a call for consensus. Do we agree to add
>>     infixr 6 <>
>>     (<>) :: Monoid m => m -> m -> m
>>     (<>) = mappend
>> If so I have a patch for base and GHC ready.

NO please don't do that. It would break all packages
that do, or soon will, use the semigroups

That proposal is no longer relevant. Every Monoid
instance should now be made an instance of
Semigroup. Anyone who wants to use <> should
import it from there.


More information about the Libraries mailing list