Re: [ghc-steering-committee] Language Extension Policy – Round 2

Dear all, A (very belated) thank you for the interesting conversation on this thread. I'm being very slow, but I'm still digesting the contents. I've tallied the answer on the questionnaire in this spreadsheet, that I've tried to make as helpful as possible (if only for my benefit, as I'm trying to make it speak) https://docs.google.com/spreadsheets/d/1cRTJ2go5opXjIp-kojR_eOA-RWNBq2jzmeco... The rest of the conversation, I have yet to figure out what to do, but the discussion on classifying the extensions by stability seems to intersect very much with the recent proposal that has been submitted by the Haskell Foundation's Stability Working Group don't hesitate to check it out https://github.com/ghc-proposals/ghc-proposals/pull/601 . One thing I will say is that among the respondents, there appears to be a pretty clear consensus that extensions should not be forever. I'll probably make my next round about this (if things go right, later today; but I'm loath to make any promise, considering how late I've been on the previous rounds). /Arnaud On Mon, 8 May 2023 at 13:59, Richard Eisenberg wrote:

On May 1, 2023, at 8:59 AM, Adam Gundry wrote:

* recommended (part of the language, fairly stable);

* experimental (not yet resolved one way or the other); or

* discouraged (supported primarily for backwards compatibility).

Yes! And also Simon's addition of "language variation".

My stance is (I claim) it is hard for users to navigate the current extension maze (e.g. it's pretty hard for someone to know that scary-sounding UndecidableInstances is safe to use in practice but that TypeFamilies may break their type inference, even if they never write a type family). We should strive to simplify this maze so that it's easier for our users to write effective Haskell.

One way to phrase this is "stable and liberal".

Richard _______________________________________________ ghc-steering-committee mailing list ghc-steering-committee@haskell.org https://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-steering-committee

-- Arnaud Spiwack Director, Research at https://moduscreate.com and https://tweag.io.