Updated votes, resolving all my maybes: Delta: * yes to NamedWildCards *and* PartialTypeSignatures (these are actually really useful and unless someone tells me otherwise I don't know any reason why the language with these is less principled than without. I would also -Wno-partial-type-signatures by default if that was in scope for GHC2021) * yes to TypeApplications (sure, why not) * all other maybes -> no (mainly just being conservative, we can reconsider for GHC2022 any that miss out) ## Uncontroversial extensions BangPatterns: yes BinaryLiterals: yes DataKinds: yes DeriveDataTypeable: yes DeriveGeneric: yes EmptyCase: yes ExistentialQuantification: yes FlexibleContexts: yes FlexibleInstances: yes GADTs: yes GeneralisedNewtypeDeriving: yes LambdaCase: yes MultiParamTypeClasses: yes MultiWayIf: yes NoMonomorphismRestriction: yes OverloadedStrings: yes PatternSynonyms: yes RankNTypes: yes RecordWildCards: yes ScopedTypeVariables: yes StandaloneDeriving: yes TupleSections: yes TypeFamilies: yes TypeSynonymInstances: yes NondecreasingIndentation: yes ConstrainedClassMethods: yes ConstraintKinds: yes DefaultSignatures: yes DeriveFoldable: yes DeriveFunctor: yes DeriveTraversable: yes EmptyDataDecls: yes EmptyDataDeriving: yes HexFloatLiterals: yes ImportQualifiedPost: yes InstanceSigs: yes KindSignatures: yes LiberalTypeSynonyms: yes NamedFieldPuns: yes (I don't personally like this, but I can't justify having RecordWildcards but not having this) NegativeLiterals: yes NumDecimals: yes PolyKinds: yes PostfixOperators: yes UnicodeSyntax: yes (but only the language extension, not the UI changes) ## Extensions that are implied by others, or are irrelevant: GADTSyntax: yes ExplicitForAll: yes MonadFailDesugaring: irrelevant MonoLocalBinds: yes ## Extensions that are deprecated or exist for legacy reasons: DatatypeContexts: no NPlusKPatterns: no CUSKs: no NoPatternGuards: no ForeignFunctionInterface: yes (already implied by Haskell2010, why do we have this but NoPatternGuards?) NullaryTypeClasses: no OverlappingInstances: no IncoherentInstances: no TypeInType: no ## No to extensions that are too new to include in GHC2021: QualifiedDo: no LinearTypes: no BlockArguments: no LexicalNegation: no QuantifiedConstraints: no StandaloneKindSignatures: yes (changed to yes because it's needed to replace CUSKs) StarIsType: yes (changed to yes following discussion) ## No to extensions that are opt-in by design: ApplicativeDo: no (can lead to non-deterministic behaviour with non-rule-abiding Applicative instances) PackageImports: no CPP: no DeriveLift: no (only makes sense with TemplateHaskell, which is opt-in) TemplateHaskell: no TemplateHaskellQuotes: no QuasiQuotes: no RebindableSyntax: no Safe: no Strict: no StrictData: no Trustworthy: no Unsafe: no ExtendedDefaultRules: no NoImplicitPrelude: no ## No to unsafe extensions: UndecidableInstances: no UndecidableSuperClasses: no ## No to low-level extensions, not intended to be on by default: UnboxedTuples: no UnboxedSums: no MagicHash: no UnliftedFFITypes: no UnliftedNewtypes: no GHCForeignImportPrim: no InterruptibleFFI: no ## No to record-related extensions Records are in flux, let's not do any of this in GHC2021. DisambiguateRecordFields: no DuplicateRecordFields: no NoTraditionalRecordSyntax: no OverloadedLabels: no ## The rest That leaves some tricky ones, I'm putting all these as "no" or "maybe"; we could conservatively just say "no" to all of them. I'm voting NO on these: Arrows: no (not widely used) ImplicitParams: no (not widely used; questionable semantics; functionality available with reflection package) ImpredicativeTypes: no (I don't think we want this on by default, right?) ParallelListComp: no (not widely used, most uses are covered by zip) StaticPointers: no (quite a niche extension, only really useful with Distributed Haskell) TransformListComp: no (not widely used) ViewPatterns: no (not widely used, and in my opinion not a good design) DeriveAnyClass: no (see discussion on the mailing list) Undecided (later resolved): AllowAmbiguousTypes: no TypeApplications: yes CApiFFI: no (harmless, but a bit niche) DerivingVia: no (not very widely-used, quite new) DerivingStrategies: no (not very widely-used, quite new) FunctionalDependencies: no (slightly inclined to "no", given the overlap with TypeFamilies and the lack of widespread usage) ExplicitNamespaces: no (might change, so defer?) MonadComprehensions: no (does this make error messages worse?) NamedWildCards: yes NumericUnderscores: no OverloadedLists: no (impact on error messages?) PartialTypeSignatures: yes RecursiveDo: no (but introduced by a keyword so relatively harmless) RoleAnnotations: no (not widely used, but when you need it you need it) TypeFamilyDependencies: no (not widely used, but when you need it you need it) TypeOperators: no On Mon, 7 Dec 2020 at 18:17, Joachim Breitner <mail@joachim-breitner.de> wrote:
Dear Committe,
it’s been two weeks since we started voting. We are still short one vote (Cale, release the suspsense!). But also, there are still plenty of “maybes” in your vote. I encourage you to change them to yes or no (at least for those extensions that are near the edge), so that we have more clarity on which extensions are actually worth spending emails on.
As always, the table
https://github.com/ghc-proposals/ghc-proposals/blob/ghc2021/proposals/0000-g... has the current data. (And even even got community contributions to improve its readability. Yay!)
We discussed many extensions on (and I might have missed some):
* The innnocence of PostfixOperators was pointed out, and widely appreciated * Joachim pleads for UnicodeSyntax * InstanceSigs worries seems to have been addressed, it’s on its way in * Whether OverloadedString is harmless enough. * Whether ViewPatterns are good enough (given that alternative ideas exist) * That ForeignFunctionInterfaces is actually part of Haskell2010 * That this isn’t quite the right time to ditch StarIsType * CUSKs vs. StandaloneKindSignatures * BlockArguments is liked by some, but may be too new * GADTs were advocated for a lot, but also a bit against, so not uncontroversial * Same with ExistentialQuantification * PolyKinds were advocated for (and got many votes) * ScopedTypeVariables is wanted on by default by some, despite the fact that nobody believes it’s the last word on that design corner. Alejandro argues that it’s ok to include it even if it will change in GHC202X again, but elsewhere SPJ says that GHC2021 should only include extensions we have reason to hope are stable and stay around . * Arnaud wonders about the hesitation to include FunctionalDependencies
Applying the actual quota of ⅔ out of 11, i.e. 8 votes, these would go in no matter how Cale votes:
BangPatterns, BinaryLiterals, ConstrainedClassMethods, ConstraintKinds, DeriveDataTypeable, DeriveFoldable, DeriveFunctor, DeriveGeneric, DeriveLift, DeriveTraversable, EmptyCase, EmptyDataDecls, EmptyDataDeriving, ExplicitForAll, FlexibleContexts, FlexibleInstances, GADTSyntax, GeneralisedNewtypeDeriving, HexFloatLiterals, ImportQualifiedPost, InstanceSigs, KindSignatures, MultiParamTypeClasses, NamedFieldPuns, NumericUnderscores, PolyKinds, PostfixOperators, RankNTypes, StandaloneDeriving, StarIsType, TypeApplications, TypeOperators, TypeSynonymInstances
The following have 7 votes, which is the quorum based on 10 ballots:
ExistentialQuantification, ForeignFunctionInterface, MonoLocalBinds, NegativeLiterals, RecordWildCards, StandaloneKindSignatures, TypeFamilies
And these are one vote short:
DataKinds, DerivingStrategies, GADTs, NamedWildCards, ScopedTypeVariables, TupleSections, UnicodeSyntax, ViewPatterns
Not sure how useful the list of symmetric difference report is, but here it is:
alejandro would miss: DataKinds, DerivingStrategies, FunctionalDependencies, GADTs, LambdaCase, MonadFailDesugaring, NamedWildCards, NoMonomorphismRestriction, NullaryTypeClasses, NumDecimals, OverloadedLists, OverloadedStrings, ScopedTypeVariables, TupleSections, UnicodeSyntax, ViewPatterns doesn’t want: none!
arnaud would miss: Arrows, DerivingStrategies, ExplicitNamespaces, FunctionalDependencies, GADTs, MonadFailDesugaring, PartialTypeSignatures, TypeFamilyDependencies, ViewPatterns doesn’t want: ExistentialQuantification, ImportQualifiedPost, InstanceSigs, NamedFieldPuns, PolyKinds, RankNTypes, RecordWildCards, StandaloneKindSignatures, TypeSynonymInstances
eric would miss: DataKinds, DefaultSignatures, DisambiguateRecordFields, ExplicitNamespaces, FunctionalDependencies, GADTs, MonadFailDesugaring, NamedWildCards, OverloadedLists, OverloadedStrings, PartialTypeSignatures, PatternSynonyms, RoleAnnotations, ScopedTypeVariables, TypeFamilyDependencies doesn’t want: EmptyDataDeriving, ForeignFunctionInterface
iavor would miss: BlockArguments, CApiFFI, MultiWayIf, NoMonomorphismRestriction, NullaryTypeClasses, ParallelListComp, RecursiveDo, UnicodeSyntax, UnliftedNewtypes doesn’t want: ConstrainedClassMethods, EmptyCase, ExplicitForAll, GADTSyntax, GeneralisedNewtypeDeriving, InstanceSigs, KindSignatures, MonoLocalBinds, NegativeLiterals, PolyKinds, StandaloneKindSignatures, StarIsType, TypeApplications, TypeFamilies, TypeOperators
joachim would miss: DataKinds, DerivingStrategies, DerivingVia, LambdaCase, NamedWildCards, NondecreasingIndentation, RoleAnnotations, TupleSections, UnicodeSyntax, UnliftedFFITypes, UnliftedNewtypes doesn’t want: ConstrainedClassMethods, ExistentialQuantification, TypeSynonymInstances
richard would miss: BlockArguments, DefaultSignatures, DerivingStrategies, DerivingVia, DisambiguateRecordFields, ExplicitNamespaces, LexicalNegation, NamedWildCards, NumDecimals, ParallelListComp, RoleAnnotations, TemplateHaskellQuotes, TupleSections, UnicodeSyntax, UnliftedNewtypes, ViewPatterns doesn’t want: MonoLocalBinds, NegativeLiterals, RecordWildCards, TypeFamilies
simonm would miss: DataKinds, DefaultSignatures, GADTs, LambdaCase, LiberalTypeSynonyms, MultiWayIf, NoMonomorphismRestriction, NondecreasingIndentation, NumDecimals, OverloadedStrings, PatternSynonyms, ScopedTypeVariables, TupleSections, UnicodeSyntax doesn’t want: DeriveLift, NumericUnderscores, TypeApplications, TypeOperators
spj would miss: NoMonomorphismRestriction, NullaryTypeClasses, OverloadedLists, OverloadedStrings, ParallelListComp, RecursiveDo, RoleAnnotations, ScopedTypeVariables, ViewPatterns doesn’t want: ForeignFunctionInterface, GeneralisedNewtypeDeriving, NegativeLiterals, RecordWildCards, TypeFamilies
tom would miss: BlockArguments, DataKinds, DefaultSignatures, DerivingStrategies, DerivingVia, DisambiguateRecordFields, DuplicateRecordFields, ExplicitNamespaces, FunctionalDependencies, GADTs, LambdaCase, LexicalNegation, LiberalTypeSynonyms, MagicHash, MultiWayIf, NamedWildCards, NullaryTypeClasses, NumDecimals, PackageImports, ParallelListComp, QuasiQuotes, RoleAnnotations, ScopedTypeVariables, TemplateHaskell, TemplateHaskellQuotes, TupleSections, TypeFamilyDependencies, UnboxedSums, UnboxedTuples, UnicodeSyntax, UnliftedNewtypes, ViewPatterns doesn’t want: ForeignFunctionInterface, MonoLocalBinds, StarIsType
vitaly would miss: DataKinds, DerivingStrategies, DerivingVia, GADTs, LambdaCase, MonadFailDesugaring, NamedWildCards, OverloadedLists, OverloadedStrings, ScopedTypeVariables, TupleSections, ViewPatterns doesn’t want: ExistentialQuantification, StandaloneKindSignatures
Cheers, Joachim
-- Joachim Breitner mail@joachim-breitner.de http://www.joachim-breitner.de/
_______________________________________________ ghc-steering-committee mailing list ghc-steering-committee@haskell.org https://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-steering-committee