January 2022 - ghc-steering-committee

Please review: #454 Custom type warnings
by Tom Harding 25 Jun '22

25 Jun '22

Hi all, As Joachim noted, #454 <https://github.com/ghc-proposals/ghc-proposals/pull/454> is extracted from Adam’s previous efforts with the Unsatisfiable constraint <https://github.com/ghc-proposals/ghc-proposals/pull/433> proposal (which has since been accepted). In short, it covers an interface for custom warnings, and I can already think of plenty of ways I’d use it. I’d therefore like to recommend acceptance, and discuss any issues or changes. Thanks, Tom

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Please review #451: Sized literals proposal; Shepherd: Simon M
by Richard Eisenberg 23 Apr '22

23 Apr '22

Dear Committee, This is your interim secretary speaking: Sized literals proposal, proposing syntax for literals for the new sized primitive numeric types, has been proposed by Sylvain Henry. https://github.com/ghc-proposals/ghc-proposals/pull/451 https://github.com/hsyl20/ghc-proposals/blob/sized-literals/proposals/0000-… I propose Simon M as the shepherd. Please guide us to a conclusion as outlined in https://github.com/ghc-proposals/ghc-proposals#committee-process Thanks, Richard

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#425: invisible binders in type declarations; rec: accept
by Richard Eisenberg 07 Apr '22

07 Apr '22

Hi all, I am the shepherd for proposal #425, https://github.com/ghc-proposals/ghc-proposals/pull/425, proposing to add invisible binders in type declarations. The main payload of the proposal is to allow definitions like > data Proxy @k (a :: k) = Proxy instead of today's > data Proxy (a :: k) = Proxy which has no explicit binding site for k. This new syntax solves a number of smallish syntax conundra, as very well outlined in the proposal. In addition, the proposal includes two small unrelated tweaks to the syntax of type family instances; these are points (6) and (7) in the proposal. Both changes will break some obscure (but still realistic, knowing Haskell) programs, but both fixes are backward compatible. --- I recommend acceptance. The proposal is motivated nicely (do check out the examples) and solves a real problem. The new syntax fits in with other similar features. The small cleanups to existing syntax will lead to better error messages. The one drawback, as I see it, is that this proposal includes point (5), which is a breaking change to the way type synonyms work. Right now, we can say > type P = (Proxy :: k -> Type) and GHC will infer P :: forall k. k -> Type. Under this proposal, you would have to write > type P @k = (Proxy :: k -> Type) bringing k into scope explicitly. The fix is not backward compatible, and so I think this proposal should come with a migration strategy, where we warn about the former version for some releases before banning it. (Continuing to support it is possible, but it's very awkward to have a variable mentioned only in a synonym's right-hand side.) Sorry for the delay in producing this recommendation! Richard

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Please review #475: New tuple and list syntax, Shepherd: Vlad
by Joachim Breitner 24 Mar '22

24 Mar '22

Dear Committee, New syntax for tuples and lists to remove punning has been resubmitted by Richard https://github.com/ghc-proposals/ghc-proposals/pull/475 https://github.com/goldfirere/ghc-proposals/blob/tuple-syntax/proposals/000… Please guide us to a conclusion as outlined in https://github.com/ghc-proposals/ghc-proposals#committee-process Thanks, Joachim -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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#270: Support pun-free code, recommendation: accept
by Vitaly Bragilevsky 14 Feb '22

14 Feb '22

Dear Committee, Proposal #270 "Support pun-free code" has been resubmitted by Artyom Kuznetsov. https://github.com/ghc-proposals/ghc-proposals/pull/270 https://github.com/hithroc/ghc-proposals/blob/master/proposals/0000-support… This proposal was heavily revised since Iavor recommended rejection. As of now, it is quite thin suggesting just a couple of things: - warnings for the code with panning (understood as using same names for both types and values) - a syntax change for import declarations to reflect which names (types or values) are actually imported when importing from libraries relied on punning. The first change promotes a new style of writing Haskell code without distinguishing types and values and having a single unified namespace. We are already on that road anyway and I don't see any reason not to support this. The second change allows using an old style with punning. It could lead to doubling import declarations, but I don't think that this is really a problem. I think the proposal is mature enough so I recommend acceptance. We can also decide on the actual word used in import declarations (data, value, or pattern). I personally prefer value, but I don't see this issue as something important. Vitaly

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Request for Nominations to the GHC Steering Committee
by Joachim Breitner 29 Jan '22

29 Jan '22

Dear Haskell community, the GHC Steering committee is seeking nominations for at least two new members. The committee scrutinizes, nitpicks, improves, weights and eventually accepts or rejects proposals that extend or change the language supported by GHC and other (public-facing) aspects of GHC. Our processes are described at https://github.com/ghc-proposals/ghc-proposals which is also the GitHub repository where proposals are proposed. In particular, please have a look at the bylaws at https://github.com/ghc-proposals/ghc-proposals/blob/master/committee.rst We are looking for a member who has the ability * to understand such language extension proposals, * to find holes and missing corner cases in the specifications, * foresee the interaction with other language features and specifications, * comment constructively and improve the proposals, * judge the cost/benefit ratio and * finally come to a justifiable conclusion. We look for committee members who have some of these properties: * have substantial experience in writing Haskell applications or libraries, which they can use to inform judgements about the utility or otherwise of proposed features, * have made active contributions to the Haskell community, for some time, * have expertise in language design and implementation, in either Haskell or related languages, which they can share with us. The committee’s work requires a small, but non-trivial amount of time, especially when you are assigned a proposal for shepherding. We estimate the workload to be around 2 hours per week, and our process works best if members usually respond to technical emails within 1-2 weeks (within days is even better). Please keep that in mind if your email inbox is already overflowing. There is no shortage of people who are eager to get fancy new features into the language, both in the committee and the wider community. But each new feature imposes a cost, to implement, to learn, (particularly) through its unexpected interaction with other features. We need to strike a balance, one that encourages innovation (as GHC always has) while still making Haskell attractive for real-world production use and for teaching. We therefore explicitly invite “conservative” members of the community to join the committee. To make a nomination, please send an email to me (as the committee secretary) at mail(a)joachim-breitner.de until February 11th. I will distribute the nominations among the committee, and we will keep the nominations and our deliberations private. We explicitly encourage self-nominations. You can nominate others, but please obtain their explicit consent to do so. (We don’t want to choose someone who turns out to be unable to serve.) On behalf of the committee, Joachim Breitner -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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Call for nominations coming up
by Joachim Breitner 29 Jan '22

29 Jan '22

Dear Committee, after Alejandro’s resignation I was checking if we have to do a new call for nominations, and at first I thought no, because we are still 9, but then I noticed that we actually missed the end of Vitaly and Eric’s three year terms, which started in Sep 2018 (time flies). So as per our bylaws, I should put out a call for nominations. Vitaly and Eric are of course welcome (and encouraged, if I may add) to re- nominated themselves. Or each other, if they like :-) Cheers, Joachim -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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Farewell Alejandro
by Joachim Breitner 29 Jan '22

29 Jan '22

Hello all, Alejandro has stepped down from the committee, after having finished the PRs assigned to him (very honorable). Thanks Alejandro for two years of service, shepherding 6 proposals, four of which have been accepted, and your contributions to all the other discussions. Cheers, Joachim -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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Please review #392: Clarify modifiers design principle, Shepherd: Alejandro
by Joachim Breitner 28 Jan '22

28 Jan '22

Dear Committe, Clarify modifiers design principle has been proposed by Richard https://github.com/ghc-proposals/ghc-proposals/pull/392 This is an amendmend to #370, see the PR description for links to diffs etc. I propose Alejandro as the shepherd, as he shepherded #370 before. Please guide us to a conclusion as outlined in https://github.com/ghc-proposals/ghc-proposals#committee-process Thanks, Joachim -- -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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Please review #452: Articulate principles for GHC evolution; Shepherd: Simon PJ
by Richard Eisenberg 14 Jan '22

14 Jan '22

Dear Committee, This is your interim secretary speaking: Articulate principles for GHC evolution, proposing a new "principles" document to be added to the proposals repo, has been proposed by me. https://github.com/ghc-proposals/ghc-proposals/pull/452 https://github.com/goldfirere/ghc-proposals/blob/principles/principles.rst I propose Simon PJ as the shepherd, as this is something of a meta-proposal, appropriate for shepherding by our chair. Please guide us to a conclusion as outlined in https://github.com/ghc-proposals/ghc-proposals#committee-process <https://github.com/ghc-proposals/ghc-proposals#committee-process> Thanks, Richard

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