[GHC] #10365: Implement Semigroup as a superclass of Monoid Proposal (Phase 1) (was: Make Semigroup as a superclass of Monoid (Phase 1))

GHC ghc-devs at haskell.org
Fri Sep 11 07:18:21 UTC 2015


#10365: Implement Semigroup as a superclass of Monoid Proposal (Phase 1)
-------------------------------------+-------------------------------------
        Reporter:  gidyn             |                   Owner:  ekmett
            Type:  feature request   |                  Status:  new
        Priority:  high              |               Milestone:  7.12.1
       Component:  libraries/base    |                 Version:  7.10.1
      Resolution:                    |                Keywords:  report-
                                     |  impact
Operating System:  Unknown/Multiple  |            Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
-------------------------------------+-------------------------------------

Old description:

> Last proposed in
> http://thread.gmane.org/gmane.comp.lang.haskell.libraries/24494
>
> === Phase 1 (GHC 7.12)
>
> Phase 1 consists in (at the very least) moving `Data.Semigroup` and
> `Data.List.NonEmpty` into `base` for GHC 7.12 (aka 8.0).
>
> If there's enough time we will also implement a warning as part of the
> first phase:
>
> > Add a warning about definitions of an operator named `(<>)` that
> indicate it will be coming into Prelude in 7.14. We should warn about
> missing Semigroup instances at any use site of `(<>)` as they'll break in
> 7.14.
>
> The rest of the migration roadmap is outlined in
> http://permalink.gmane.org/gmane.comp.lang.haskell.libraries/24526

New description:

 More details in Proposal/SemigroupMonoid

 === Phase 1 (GHC 7.12)

 Phase 1 consists in (at the very least) moving `Data.Semigroup` and
 `Data.List.NonEmpty` into `base` for GHC 7.12 (aka 8.0).

 If there's enough time we will also implement a warning as part of the
 first phase:

 > Add a warning about definitions of an operator named `(<>)` that
 indicate it will be coming into Prelude in 7.14. We should warn about
 missing Semigroup instances at any use site of `(<>)` as they'll break in
 7.14.

--

Comment (by hvr):

 added link to new Proposal/SemigroupMonoid wiki page (still a draft)

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10365#comment:6>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler


More information about the ghc-tickets mailing list