April 2025 - ghc-steering-committee

Please review #632: introduction of new language editions (inc. GHC2024)
by Adam Gundry 14 Apr '25

14 Apr '25

Dear Committee, I propose to amend the process for introducing new language editions, such that GHC always uses the latest language edition by default. In particular this would change the default language edition to GHC2024 (it currently remains GHC2021): https://github.com/ghc-proposals/ghc-proposals/pull/632 https://github.com/adamgundry/ghc-proposals/blob/ghc2024-amendment/proposal… https://github.com/adamgundry/ghc-proposals/blob/ghc2024-amendment/proposal… I'd like to invite Simon Marlow to be the shepherd. (Originally I was shepherding this amendment myself, in the hope that it would be a quick amendment in time for GHC 9.10, but that was clearly a forlorn hope!) Please guide us to a conclusion as outlined in https://github.com/ghc-proposals/ghc-proposals#committee-process Cheers, Adam -- Adam Gundry, Haskell Consultant Well-Typed LLP, https://www.well-typed.com/ Registered in England & Wales, OC335890 27 Old Gloucester Street, London WC1N 3AX, England

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Re: [ghc-steering-committee] #668: Allow reserved identifiers as fields in OverloadedRecordDot, recommendation: accept
by Sebastian Graf 14 Apr '25

14 Apr '25

I vote B > A > C > D as well, barring resolution of a small confusion I raised in the proposal discussion.

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Please review #687: Monad of No Return
by Adam Gundry 13 Apr '25

13 Apr '25

Dear Committee, Benjamin proposes to revive and move forward the Monad of No Return proposal: https://github.com/ghc-proposals/ghc-proposals/pull/687 https://github.com/L0neGamer/ghc-proposals/blob/amending-mrp/proposals/0000… I'd like to nominate Matthías as the shepherd. Please guide us to a conclusion as outlined in https://github.com/ghc-proposals/ghc-proposals#committee-process Cheers, Adam -- Adam Gundry, Haskell Consultant Well-Typed LLP, https://www.well-typed.com/ Registered in England & Wales, OC335890 27 Old Gloucester Street, London WC1N 3AX, England

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#668: Allow reserved identifiers as fields in OverloadedRecordDot, recommendation: accept
by Adam Gundry 11 Apr '25

11 Apr '25

Dear Committee, In the interests of getting things moving on proposal #668 from Matt Parsons, I'll shepherd it myself, and recommend we accept it. https://github.com/ghc-proposals/ghc-proposals/pull/668 This is a small amendment to the OverloadedRecordDot extension to allow reserved identifiers as field names. For example, this program is currently rejected with a parse error, but would be accepted: import GHC.Records x = foo.type -- parse error, "type" is a reserved identifier data T = MkT Int foo = MkT 42 instance HasField "type" T Int where getField (MkT x) = x While "type" is not a valid field name in a traditional Haskell record data type, there is nothing stopping a user defining their own instance for `HasField "type" r a`, and some users would like to do so (e.g. when using HasField to interface with a database). Attempting to use such an instance with OverloadedRecordDot runs into this parse error. However the presence of the dot syntax means there is no ambiguity in what the user means. Even if a user wrote `x.type` by accident, they are likely to get better diagnostic information if the parser accepts the program. The only issue I see is that some syntax highlighters unaware of this change may incorrectly highlight such record projections as keywords. Please indicate whether you are happy to accept this proposal. Cheers, Adam -- Adam Gundry, Haskell Consultant Well-Typed LLP, https://www.well-typed.com/ Registered in England & Wales, OC335890 27 Old Gloucester Street, London WC1N 3AX, England

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