exactprint prototype, barbie approach by leana8959 · Pull Request #11690 · haskell/cabal

leana8959 · 2026-04-02T07:59:40Z

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fix build error don't allow other types as modifiers stop using undecidable instances rewrite condtree as barbie rewrite condbranch as barbie fix build add ExactParsec class simple example for dependency make PackageName a barbie fix build pass down modifier to package name barbie update Dependency's ExactParsec instance complete PackageName exactparse proof of concept use exactparsec to define parsec parameterize VersionRange parameterize Version pass down modifier to version barbie remove ExactParsec class Rename Barbie -> With, WithTrivia -> Ann implement VersionRangeAnn Parsec instance define Parsec without ann remodel trivia representation remodel version range fix trailing / leading string implement pretty VersionRangeAnn use VersionRangeAnn in DependencyAnn implement pretty DependencyAnn parameterize BuildInfo parameterize Library parameterize GenericPackageDescription refactor modify rename type variable for consistency Modifiers now have kind type make buildinfo lens polymorphic update codebase to match HasBuildInfo change introduce constraint alias fix compilation run formatter implement Ann variant of HasBuildInfoWith class make buildInfoFieldGrammar generic make optionsFieldGrammar generic make profOptionsfieldGrammar generic make sharedOptionsFieldGrammar generic make profSharedOptionsFieldGrammar generic make hsSourceDirsGrammar generic export GenericPackageDescriptionAnn alias run formatter clean up make library's lens polymorphic make libraryFieldGrammar polymorphic add dependency parsec/pretty instance tests complete dependency roundtrip refactor cabal versioned tests test entirety of cabal dependency specification parameterize newtype combinators fix compile errors make testcases names more descriptive implement trivia-aware commavcat run fourmolu fix warnings implement trivia-aware commafcat implement trivia-aware vcatann run fourmolu implement trivia-aware fsepann implement trivia-aware NoCommaFSepAnn only guard ^>= bound test behind cabal version 2 implement parsec instance of trivia-aware polymorphic list combinator implement pretty instance of trivia-aware list combinator add all tests for combinators fix VCatAnn and FSepAnn leading trivia parsing fix VCatAnn and FSepAnn optional comma fix CommaVCatAnn and CommaFSepAnn trailing correct parsec pretty test names factor out parsecSpaceAnn pattern include position in trivia model refactor cabal-syntax to use DataKinds This makes the modifier closed fix project wide compilation errors create PrettPos as subclass of Pretty add todos Revert "create PrettPos as subclass of Pretty" Retrieve stored position from the Pretty instances and pass them to FieldGrammar. What was tried: - [x] MultiParamTypeClasses Breaking all downstream instances due to instance head change. - [x] TypeFamilies: Impossible to use injectivity because one modifier has more than one `a`. Otherwise requires all sites to define the associated type modifier. - [x] PrettyPos as subclass of Pretty. Use PrettyPos in FieldGrammar. Enforces all field grammar to have position. Not all of them have position. - [ ] Combine MultiParamTypeClasses and PrettyPos subclass: Flexibility: not all field grammar need to have the same output type. No breakage: downstream instance heads aren't changed. We create a new class. make trivia type parameterized In some situations we want to pass around not only the whitespaces trivia, but also Position. This makes it possible to reuse the Trivia type for Position. implement model for position tracking WIP: figure out how to thread position in field grammar implement example of build depends with positions implement pretty version of field grammar make targetBuildDepends field hold position if needed field BuildInfo type family simplify TargetBuildDepends type class mini example of field grammar with position retention checkpoint checkpoint conversion example allow contramapping field grammar and leave some notes attepmt to make position registering also controllable in field grammar attempt to parameterize field gramamr output implement field grammar fully generically Split out Annotate type family move AttachPos type family remove TargetBuildDepends type family rewrite with proxy introduce one more type argument in Field Grammar add a field to attepmt polymorphic monoidalFieldAla output reimplement minibuildinfo with generic monoidalFieldAla' implement monoidalFieldAla' export miniBuildInfoFieldGrammar for a demo implement demo for miniBuildInfoDemo add note demonstrate that NoAnn works implement buildable field in BuildInfo implement buildable split AttachPos into AttachPos and PreserveGrouping implement buildTools remove some redundant type application implement BuildtoolDepends use mod to choose ListWith instance fix buildinfo example add cppOptions field add asmOptions field add cmmOptions field inline newtypes with new helpers test out specialization idea add ccOptions field add cxxOptions field implement jsppOptions add ldOptions field add hsc2hsOptions field add pkgConfigDependency field stuck at frameworks field implement framework field add extraFrameworkDirs field add asmSources field add cmmSources field add cSources field add cxxSources field add jsSources field add hsSourceDirs field make hsSourceDirs polymorphic /and/ backward compatible add other modules field example implementation of printer monoidalFieldAla attach trivia to boolean relax pretty field grammar output type leave some notes insert real position in cabalparsec and parsecparser thread through real offsetted position remodel buildable boolean field annotation - position can never appear when inserted - there is no string annotation (we ignore the casing here because warning means the cabal file is not valid) remove random comment push out fieldname position run fourmolu distinguish AttachPositions and AttachPosition patch pretty for now so it builds and runs most tests fine test displaying mini build info, add note about model add parsec combinator to store position register each element's position in list combinators fix minibuildinfo register each field position for hsSourceDirs make buildinfofieldgrammar' polymorphic again remove unused prototype methods leave notes for newtype ListWith update comments on future direction regarding pretty include ExactDoc module from trivia tree attempt for full roundtrip reimplement prettyfield to exactdoc demonstrate roundtrip in cli add a small cabal file test XXX tree-wide change is necessary to parse with current entrypoint To parse with parseGenericPackageDescription, it is necessary to use buildInfoFieldGrammar. However, it is not yet fully generic. Revert "XXX tree-wide change is necessary to parse with current entrypoint" This reverts commit d3e5d79. update buildinfofieldgrammar' to compile again parse all fields of build info rewire buildinfofieldgrammar polymorphize libraryFieldGrammar checkpoint fully generalize goSection && parseGenericParsecDescription fix test suite compilation run parser against hackage implement smallCabalFile test implement part of ppGenericPackageDescriptionAnn did thing repair boolean field! Implement position preserving optionalfieldAla' implement position preserving optionalfieldala' (printer) preserve cabal-version position make uniqueField polymorphic implement parsec implement pretty use uniqueField in pkgName use uniqueField in pkgVersion filter out zeroPos fields for now render pretty fields with exactdoc retain section position push out section position to pretty field (WIP) float out position in pretty printer float out positions from condtrees inject lens into pretty printer when running add field to Library to store section position add lens for the aforementioned field add method to parser to register section position change printer to use this lens rewire the parser to insert the position properly provide lens in printing functions make lens' focus polymorphic rewrite with Maybe for post section position insertion store section position in condtree library retrieve section position from sub library clean up previous experiments some clean up and prepare smallCabalFile for demo try hackage roundtrip tests remove dead code run fourmolu refactor modules rename modifiers simplify type families add experimental type aliases add type alias for ParsecFieldGrammar add type alias for PrettyFieldGrammar fix ParsecFG compilation errors fix some export/import errors fix test import mark -any as inserted test -any and -none fix hackage tests add backward compatible method stubs for now restore TestSuite parsing and validation restore Benchmark parsing and validation restore specialization pragma use MonoidalFieldAla alias refactor hssourcedirconstraint use monolocalbind fix most compilation warnings clean up constraints refactor constraints run fourmolu restore buildinfofieldgrammar constraints remove redundant constraints remove redundant constraints push out gpd validation, validate only abst syntax remove redundant constraints restore validation restore error message restore mixins version guard update golden test files use compact diff when displaying errors run fourmolu clean up and fix test suite compilation

…a sumtype

leana8959 force-pushed the gpd-barbie branch 2 times, most recently from 4533c76 to cb2fa93 Compare April 7, 2026 13:31

leana8959 force-pushed the gpd-barbie branch 2 times, most recently from 1853c00 to 16b1779 Compare May 13, 2026 14:03

leana8959 added 4 commits May 13, 2026 16:44

feat: implement comment parser

9572b79

remove redundant constraints

53108c2

add -Wredundant-constraints to cabal-install

5def3e8

leana8959 force-pushed the gpd-barbie branch from 16b1779 to bb132d5 Compare May 13, 2026 14:44

move applicative bounds

7f8ddd6

ulysses4ever mentioned this pull request May 14, 2026

Comment parser #11252

Open

6 tasks

leana8959 added 12 commits May 19, 2026 10:53

feed Field (WithComments Position) to field grammar parser

3f150f9

update goSection to accept Fields (WithComments Position)

e278856

adapt runParsecParser to take in fieldstream with comment annotations

7ec4168

use StreamBody to alternate between fieldline and comment

1341548

add a comment in smallCabalFile

840ed34

add a newtype for a new Parsec of ParsecParser instance that outputs …

2e09fbf

…a sumtype

define CharParsing for FlsAnnToken

2e9dd71

consistent naming

2aa738e

ParsecParserAnn implement comment parsing

627499a

add example for fieldline parsing with comments

0bdc558

implement dependency parser

d0c6a47

demo printing a data with comments attached to it

63d4e83

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exactprint prototype, barbie approach#11690

exactprint prototype, barbie approach#11690
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leana8959 commented Apr 2, 2026

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leana8959 commented Apr 2, 2026

Uh oh!

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