- ghc-steering-committee

#515 Relaxing HasField constraints, reassigned to Moritz
by Joachim Breitner 10 Feb '23

10 Feb '23

Hi committee, with Tom stepping down, we have to re-assign this proposal: #515 Relaxing HasField constraints https://github.com/ghc-proposals/ghc-proposals/pull/515 https://github.com/ocharles/ghc-proposals/blob/hasfield/proposals/0000-hasf… It was submitted in August 2022, and Tom recommended acceptance. Richard raised technical issues with it. I’d like to assign it to Adam, but he’s a co-author… So in best tradition of our committee, I’ll assign this to Moritz. Moritz, can you help drive the discussion, here and/or on Github? Maybe the proposal needs to be revised, based on Richard’s objections? Then you can label it as “needs-revision” until the authors come back to you. Cheers, Joachim -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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Thanks, Tom!
by Joachim Breitner 10 Feb '23

10 Feb '23

Hi, Tom told me that it’s time for him to step down. Thanks, Tom, for your service on the committee in the last three years, and don’t be a stranger to GHC! (Tom was an “expiring member” anyways since January, but we are still 10 members strong, so this does not trigger a new call for nominations. The next regular call for nomination will happen next spring when Richard’s, Vlad’s and my terms expire.) Cheers, Joachim -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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Welcome Moritz Angermann
by Joachim Breitner 09 Feb '23

09 Feb '23

Hello everybody, the committee welcomes Moritz Angermann as our newest member! Cheers, Joachim -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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Fast tracked amendment: Warning category syntax (#576)
by Joachim Breitner 05 Feb '23

05 Feb '23

Hi, implementation work on warning categories (#541) shows that the implementation would be much simpler if the category was lexed as a string literal, and Adam wants to amend his warning category proposal to the syntax {-# WARNING in "x-some-category" "message" #-} This amendment is at https://github.com/ghc-proposals/ghc-proposals/pull/576. This seems to be changing a minor aspect of the original proposal and implementation is ready, so I think we can fast-track accepting this. If you disagree with this process please complain until the end of the week (Sun Feb 5). Cheers, Joachim -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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Fast tracked amendment: No #. label (#573)
by Joachim Breitner 05 Feb '23

05 Feb '23

Hi, implementation work on #170 led to insights that called for small adjustments to the design, namely to remove dot from characters allowed in overloaded labels. The proposal is amended at https://github.com/ghc-proposals/ghc-proposals/pull/573. This should be part of 9.6, so I’d like to fast-track this for acceptance. If you disagree with this process please complain until the end of the week (Sun Feb 5). Cheers, Joachim -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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By-law change: Allow self-nominations
by Joachim Breitner 05 Feb '23

05 Feb '23

Hi, our current by-law kinda bind our hands in case some motivated comes along and would like to join the committee, and Simon PJ suggested that we should give us the discretion to hold membership votes out-of-season as well. The suggested wording change is in https://github.com/ghc-proposals/ghc-proposals/pull/572 Please discuss and cast your vote within two weeks (preferably earlier, as you can guess this change is not happening completely out of the blue.) I’m in favor. Cheers, Joachim -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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Re: [ghc-steering-committee] By-law change: Allow self-nominations
by Arnaud Spiwack 30 Jan '23

30 Jan '23

Spam detection software, running on the system "mail.haskell.org", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see @@CONTACT_ADDRESS@@ for details. Content preview: I've posted comments on the Github thread, to try and clarify a few points before I cast my vote. On Thu, 26 Jan 2023 at 03:02, Richard Eisenberg <lists(a)richarde.dev> wrote: > Spam detection software, running on the system "mail.haskell.org", has > identified this incoming email as possible spam. The original message > has been attached to this so you can view it (if it isn't spam) or label > similar future email. If you have any questions, see > @@CONTACT_ADDRESS@@ for details. > > Content preview: +1 from me, too > On Jan 23, 2023, at 1:27 PM, Chris > Dornan > <chris(a)chrisdornan.com> wrote: > > +1 to this proposed change to the > nominations > process. > >> On 2023-01-23, at 14:24, Joachim Breitner < > mail(a)joachim-breitner.de> > wrote: >> >> Hi, >> >> our current by-law kinda bind our hands in case > some > motivated comes >> along and would like to join the committee, and Simon > PJ suggested that >> we should give us the discretion to hold membership > votes > out-of-season >> as well. The suggested wording change is in >> > https://github.com/ghc-proposals/ghc-proposals/pull/572 > >> >> Please discuss and cast your vote within two weeks (preferably > earlier, > >> as you can guess this change is not happening completely out of the > >> > blue.) >> >> Iâm in favor. >> >> Cheers, >> Joachim >> >> >> -- >> > Joachim > Breitner >> mail(a)joachim-breitner.de >> http://www.joachim-breitner.de/ > >> > >> >> ghc-steering-committee mailing list >> > ghc-steering-committee(a)haskell.org > >> > https://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-steering-committee > > > > ghc-steering-committee mailing list > > ghc-steering-committee(a)haskell.org > > > https://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-steering-committee > [...] > > Content analysis details: (5.0 points, 5.0 required) > > pts rule name description > ---- > > -0.0 SPF_HELO_PASS SPF: HELO matches SPF record > 5.0 UNWANTED_LANGUAGE_BODY BODY: Message written in an undesired language > 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid > > > > > > Forwarded message > From: Richard Eisenberg <lists(a)richarde.dev> > [...] Content analysis details: (5.8 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 SPF_PASS SPF: sender matches SPF record 5.0 UNWANTED_LANGUAGE_BODY BODY: Message written in an undesired language 0.0 HTML_MESSAGE BODY: HTML included in message 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% [score: 0.5000] 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid The original message was not completely plain text, and may be unsafe to open with some email clients; in particular, it may contain a virus, or confirm that your address can receive spam. If you wish to view it, it may be safer to save it to a file and open it with an editor.

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#555: Higher Order Patterns in Rewrite Rules, rec accept
by Joachim Breitner 23 Jan '23

23 Jan '23

Dear Committee, Jaro Reinders and Simon PJ propose to allow Higher Order Patterns in Rewrite Rules. The idea, by way of an example, {-# RULES forall f. foo (\y. f y + f y) = bar f #-} will now not only match "foo (\y. negate y + negate y)" (with f set to negate) but also "foo (\y. y*y + y*y)" (with f set to (\x. x*x)). Here "f y" is a higher-order pattern, which are restricted to a _pattern_ variable followed by a list of _local_ variable, indicating which variable the matched expression may depend on (previously, only closed expressions could be matched). An implementation is sitting ready at https://gitlab.haskell.org/ghc/ghc/-/merge_requests/9343 The design was carefully crafted to be backward-compatible and not introduce spurious etwa-expansion where there was non before. It is not guarded by a LANGUAGE pragma (but RULES themselves are not). Library authors who care about backward compat will have to deal with CPP pragmas. I’m a big fan of rewrite rules, and the proposal is straight forward and provides a feature that I'd maybe optimistically already assumed to be there already. Therefore, I’m recommending acceptance. If you disagree please speak up within two weeks, or speed up the process by indicating agreement earlier. Cheers, Joachim -- Joachim Breitner mail(a)joachim-breitner.de http://www.joachim-breitner.de/

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Fwd: GHC2023
by Simon Peyton Jones 20 Jan '23

20 Jan '23

Dear Ghc-Steering-Committee, Here's an email from Tom Ellis about the GHC20xx thread. Please do read it. (Who, if anyone, is the moderator of the ghc-steering-committee mailing list?) Simon ---------- Forwarded message --------- From: Tom Ellis <tom-2019(a)jaguarpaw.co.uk> Date: Tue, 8 Nov 2022 at 08:04 Subject: Re: [ghc-steering-committee] GHC2023 To: Simon Peyton Jones <simon.peytonjones(a)gmail.com> Hello Simon, I sent this to the steering committee mailing list on Saturday but received an email in response saying it was "being held until the list moderator can review it for approval". Perhaps no moderator has had the chance to review it yet, as it hasn't yet appeared on the mailing list archive https://mail.haskell.org/pipermail/ghc-steering-committee/2022-November/thr… Perhaps you would be kind enough to forward it to the list for me directly. Thanks, Tom Thanks Simon. On reflection, I'm not particularly motivated to consult the community because the concerns I have impinge most strongly on members of the community who are distant from where a consultation could easily reach, and on non-but-potential-members of the community who are getting a false impression from afar. I will content myself with elaborating on my concerns and then leaving it to the steering committee to take them into account if they see fit. To set the scene, everything I write below is presented from the point of view of someone who wishes Haskell usage to increase and believes that we can't increase Haskell usage by appealing to people who are already comfortable with the way the Haskell ecosystem currently works: we've already got most of those people. For the ten years that I have been in the community, Haskell has had a (false) reputation, to outsiders, as a fragmented language with multiple mysterious things called "language extensions" each of which fractures the language in an incompatible way. "It's impossible to learn Haskell because there are so many incompatible Haskells" they say. It may be hard to believe that this perception exists: as users of GHC we know that there are very few extensions that introduce any incompatibility with others; extensions typically just remove unneccesary restrictions. But, for those of you who don't spend far-too-much of your time on discussion fora such as Hacker News and Reddit, I can guarantee to you that this objection to Haskell comes up *a lot*. Haskell also has, to both insiders and outsiders, a (true) reputation for being an unstable moving target. "It's impossible to learn or use Haskell because the language and libraries keep changing", they say. This one is easier to believe. GHC2021 is a wonderful way of dealing with all of the first and part of the second objection! I can now respond to complaints of language fragmentation and language instability by simply saying "Turn on GHC2021 and be happy". This is great news! (GHC2021 doesn't deal with instability in libraries of course, but I'm pleased that there are many people making efforts in that area too.) I am concerned that GHC2023 would weaken the power of my rejoinder "Turn on GHC2021 and be happy". Now I am at risk of the responses "But why not GHC2023?", "Haskell introduced a new, incompatible language just two years after standardising on GHC2021", "I just spent my precious time learning GHC2021, now I have to spend time learning GHC2023.". Sure, these responses are based on misunderstandings of the technical details. But perceptions really, really matter! If we want a large increase in Haskell usage then we have to take perceptions into account. We can't substantially increase Haskell usage any more by appealing just to our techncial excellence. If we choose to prioritise business-as-usual, that is, the incorporation of highly technically excellent features on a regular basis, with no thought to the costs, then the consequence will be Haskellers-as-usual: people who value that kind of thing in spite of the costs. We already have most of those people. We can't increase Haskell adoption that way. If we choose to change tack then we have the chance of changing the types of people we pick up as new Haskellers, from among those who would never otherwise have considered the language. To put it pithily, Joachim writes in a sibling thread "The point of the GHC20xx series is to get (proven, useful, uncontroversial) goodies into the hands of our users". Are members of the Haskell community, and indeed non-but-potential-members, screaming out for new "goodies"? Or are they screaming out for a brief respite from the unforgiving churn of the Haskell ecosystem, both real and not-real-but-perceived. My experience of the last ten years tells me it's the latter. To be clear, I personally am very much looking forward to more highly technically excellent features, including the exciting ongoing work on dependent types, WASM, GHCJS, and so on. It's one of the aspects of the community that really inspires and excites me! I personally can tolerate the churn. But I don't want those things at the *cost* of continuing to push away potential new users who are currently peering over the fence, discouraged because they can't tolerate the churn that they see, real or perceived. Now, with my stability hat on, looking from the point of view of process design, it's actually *better* for changes to happen in small increments, so maybe having GHC20xx every year is actually *better* than every five years. I don't wish to advocate for one choice or another. Rather I wish to advocate for the point of view that: Technical excellence matters. Stability and the perception of stability matter too. Tom On Tue, 1 Nov 2022 at 11:43, Simon Peyton Jones <simon.peytonjones(a)gmail.com> wrote: > Another year has passed, and if we are serious with the idea that >> GHC20xx is a continuous thing, we should probably start defining >> GHC2023 – even if it is just a small delta. >> > > Indeed, we originally said we'd review GHC20xx annually, but I think we > might want to consult the community to see if that is too often. There has > been an interesting thread > <https://discourse.haskell.org/t/quo-vadis-ghc2023/5220>on the Haskell > Discourse. > > The HF Stability Working Group discussed this on Monday, and I think Tom > Ellis (a member of the SWG) is willing to lead a consultation. I think > that would be great -- we have no axe to grind here, and I think we'll be > delighted to do whatever makes the maximal number of people happy. > > Tom (cc'd) will write with more info shortly. Sound OK? > > Simon > > On Mon, 24 Oct 2022 at 20:49, Joachim Breitner <mail(a)joachim-breitner.de> > wrote: > >> Hi Committee, >> >> when we defined the process for GHC20xx, as written in >> >> https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0372-g… >> we wrote >> >> Likely, the first iteration of this process will be vastly different >> from the following ones: The first one is expected to add a large >> number of uncontroversial extensions; so the next iteration will >> likely only make a smaller, but more controversial change. >> >> Therefore, this proposal does not commit to a fixed cadence. >> Instead, 6 months after the first release of a version of GHC that >> supports a GHC20xx set, we evaluate the outcome, the process, and >> the perceived need of a next release. At that time we will refine >> the processes, if needed, and set a cadence. >> >> The first version of GHC that supported GHC2021 was 9.2, released in >> October 2022. >> >> Last fall we said that not enough time has passed to do such an >> evaluation, and we skipped defining GHC2022. >> >> Another year has passed, and if we are serious with the idea that >> GHC20xx is a continuous thing, we should probably start defining >> GHC2023 – even if it is just a small delta. This e-mail tries to >> kickstart that process. >> >> >> Last time we did a relative elaborate thing where we voted on >> essentially _every_ extension. I think that made sense for the first >> iteration, where we had to winddow down the likely extensions. But now >> we have a base line (GHC2021), and are asked to find a suitable delta, >> and I’d go for a nomination-based approach: Committee members can >> propose adding (or removing, in theory) specific extensions, and then >> we vote only on those. Does that sound reasonable? >> >> Does anyone have any insight from the real world? Has GHC2021 helped >> our users? And if not, why not? >> >> What kind of hard data would you like to see, if any? >> >> (I’m a bit wary of spending too much time writing scripts to scrape >> hackage, for example to see which extensions people tend to enable _in >> addition_ to GHC2021, only to see that libraries on hackage are >> understandably slow to use default-language: GHC2021, as that’s not >> great for backward compat for now. But I am also not sure where to look >> for good data…)

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please accept "Make Symbol a newtype over String"
by Chris Dornan 20 Jan '23

20 Jan '23

While we are at it, here is another proposal that I think should be straightforward. Oleg has proposed that we do essentially the same trick Richard proposed to unify Nat and Natural, but with Symbol and String. Specifically, he is proposing that we replace @data Symbol@ with @newtype Symbol = MkSymbol String@. I won't try and encapsulate any further -- the original is concise and clear. * Oleg's "Make Symbol a newtype over String" proposal: https://github.com/ghc-proposals/ghc-proposals/blob/symbol-type/proposals/0… * For comparison, Richard's accepted "Unify Nat and Natural" proposal: https://github.com/goldfirere/ghc-proposals/blob/natural/proposals/0000-uni… I suggest we allow the usual two weeks to speak or forever hold your peace. Chris

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