[ghc-steering-committee] Proposal: Type Fixity (#65), Recommendation: Reject

[Simon Peyton Jones]

If you see my comment
https://github.com/ghc-proposals/ghc-proposals/pull/65#issuecomment-325301080
you'll see that I finally realised that GHC (and indeed H98) /already/ allows different fixities for term and type level.

So now I'm more supportive: it's become /solely/ a question of whether we supply concrete syntax to allow us to do something on one module that we can /already/ do (perhaps inconveniently) with two.

So I'm now mildly in favour.

Simon

|  -----Original Message-----
|  From: ghc-steering-committee [mailto:ghc-steering-committee-
|  bounces at haskell.org] On Behalf Of Joachim Breitner
|  Sent: 20 September 2017 17:24
|  To: ghc-steering-committee at haskell.org
|  Subject: Re: [ghc-steering-committee] Proposal: Type Fixity (#65),
|  Recommendation: Reject
|  
|  Hi,
|  
|  the type fixity proposal
|  (https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com
|  %2Fghc-proposals%2Fghc-
|  proposals%2Fpull%2F65&data=02%7C01%7Csimonpj%40microsoft.com%7Cc0583aed4fbd4
|  f37a40a08d500441d81%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C63641521490
|  8671210&sdata=%2F9oJkejSngjz%2FGy12Q%2FJlPOzzFdT%2FHD9SslPffMcA60%3D&reserve
|  d=0)
|  was met with mixed reactions.
|  
|   * I recommended rejection and Manuel strongly agrees with me.
|   * SPJ does not have strong opinions either way.
|   * Richard is in favor, and Iavor agrees.
|  
|  
|  Our process says “If consensus is elusive, then we vote, with the Simons
|  retaining veto power.” It looks like this might be such a case.
|  Should we go ahead and vote, or is more discussion likely to sway some of
|  us?
|  
|  (I guess I can be swayed towards acceptance, especially if this proposal re-
|  uses existing syntactic idioms from export lists with ExplicitNamespaces
|  on.)
|  
|  Greetings,
|  Joachim
|  
|  
|  
|  Am Sonntag, den 27.08.2017, 20:16 +0200 schrieb Joachim Breitner:
|  > Dear Committee,
|  >
|  > Ryan Scott’s proposal to allow fixity declaration to explicitly target
|  > values or types has been brought before us:
|  > https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithu
|  > b.com%2FRyanGlScott%2Fghc-proposals%2Fblob%2Ftype-infix%2F0000-type-in
|  > fix.rst&data=02%7C01%7Csimonpj%40microsoft.com%7Cc0583aed4fbd4f37a40a0
|  > 8d500441d81%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C6364152149086
|  > 71210&sdata=1qRrPKmHWYpB9XRFOHwiJT2Kwc%2B%2BOtf0vm0ibOWuTQI%3D&reserve
|  > d=0
|  > https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithu
|  > b.com%2Fghc-proposals%2Fghc-proposals%2Fpull%2F65&data=02%7C01%7Csimon
|  > pj%40microsoft.com%7Cc0583aed4fbd4f37a40a08d500441d81%7C72f988bf86f141
|  > af91ab2d7cd011db47%7C1%7C0%7C636415214908671210&sdata=%2F9oJkejSngjz%2
|  > FGy12Q%2FJlPOzzFdT%2FHD9SslPffMcA60%3D&reserved=0
|  >
|  > I (the secretary) nominates myself as the shepherd, so I can right
|  > away continue giving a recommendation.
|  >
|  > I propose to reject this proposal. The main reasons are:
|  >  * it is not clear if there is a real use case for this. Has anyone
|  >    ever complained about the status quo?
|  >    The proposal does not motivate the need for a change well enough.
|  >    (There is a related bug in TH, but that bug can probably simply be
|  >    fixed.)
|  >  * The status quo can be sold as a feature, rather than a short-coming.
|  >    Namely that an operator has a fixed fixity, no matter what namespace
|  >    it lives in.
|  >    This matches morally what other languages do: In Gallina, fixity
|  >    is assigned to names independent of their definition, AFAIK.
|  >  * There is a non-trivial implementation and education overhead, a
|  >    weight that is not pulled by the gains.
|  >
|  > If we’d design Haskell from scratch, my verdict might possibly be
|  > different (but maybe we wouldn’t even allow types and values to share
|  > names then…)
|  >
|  >
|  > Please contradict me or indicate consensus by staying silent.
|  >
|  >
|  > Greetings,
|  > Joachim
|  >
|  > _______________________________________________
|  > ghc-steering-committee mailing list
|  > ghc-steering-committee at haskell.org
|  > https://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-steering-committ
|  > ee
|  --
|  Joachim Breitner
|    mail at joachim-breitner.de
|  
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|  
|  --
|  Joachim “nomeata” Breitner
|    mail at joachim-breitner.de
|  
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