summaryrefslogtreecommitdiff
path: root/compiler/GHC/Parser
Commit message (Collapse)AuthorAgeFilesLines
* Implement record dot syntaxwip/joachim/bump-haddockShayne Fletcher2021-03-064-32/+180
|
* Wrap LHsContext in Maybe in the GHC ASTAlan Zimmerman2021-03-013-7/+6
| | | | | | | If the context is missing it is captured as Nothing, rather than putting a noLoc in the ParsedSource. Updates haddock submodule
* Fix typechecking time bug for large rationals (#15646)Andreas Klebinger2021-02-271-13/+15
| | | | | | | | | When desugaring large overloaded literals we now avoid computing the `Rational` value. Instead prefering to store the significant and exponent as given where reasonable and possible. See Note [FractionalLit representation] for details.
* Improve handling of overloaded labels, literals, lists etcwip/T19154Simon Peyton Jones2021-02-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When implementing Quick Look I'd failed to remember that overloaded labels, like #foo, should be treated as a "head", so that they can be instantiated with Visible Type Application. This caused #19154. A very similar ticket covers overloaded literals: #19167. This patch fixes both problems, but (annoyingly, albeit temporarily) in two different ways. Overloaded labels I dealt with overloaded labels by buying fully into the Rebindable Syntax approach described in GHC.Hs.Expr Note [Rebindable syntax and HsExpansion]. There is a good overview in GHC.Rename.Expr Note [Handling overloaded and rebindable constructs]. That module contains much of the payload for this patch. Specifically: * Overloaded labels are expanded in the renamer, fixing #19154. See Note [Overloaded labels] in GHC.Rename.Expr. * Left and right sections used to have special code paths in the typechecker and desugarer. Now we just expand them in the renamer. This is harder than it sounds. See GHC.Rename.Expr Note [Left and right sections]. * Infix operator applications are expanded in the typechecker, specifically in GHC.Tc.Gen.App.splitHsApps. See Note [Desugar OpApp in the typechecker] in that module * ExplicitLists are expanded in the renamer, when (and only when) OverloadedLists is on. * HsIf is expanded in the renamer when (and only when) RebindableSyntax is on. Reason: the coverage checker treats HsIf specially. Maybe we could instead expand it unconditionally, and fix up the coverage checker, but I did not attempt that. Overloaded literals Overloaded literals, like numbers (3, 4.2) and strings with OverloadedStrings, were not working correctly with explicit type applications (see #19167). Ideally I'd also expand them in the renamer, like the stuff above, but I drew back on that because they can occur in HsPat as well, and I did not want to to do the HsExpanded thing for patterns. But they *can* now be the "head" of an application in the typechecker, and hence something like ("foo" @T) works now. See GHC.Tc.Gen.Head.tcInferOverLit. It's also done a bit more elegantly, rather than by constructing a new HsExpr and re-invoking the typechecker. There is some refactoring around tcShortCutLit. Ultimately there is more to do here, following the Rebindable Syntax story. There are a lot of knock-on effects: * HsOverLabel and ExplicitList no longer need funny (Maybe SyntaxExpr) fields to support rebindable syntax -- good! * HsOverLabel, OpApp, SectionL, SectionR all become impossible in the output of the typecheker, GhcTc; so we set their extension fields to Void. See GHC.Hs.Expr Note [Constructor cannot occur] * Template Haskell quotes for HsExpanded is a bit tricky. See Note [Quotation and rebindable syntax] in GHC.HsToCore.Quote. * In GHC.HsToCore.Match.viewLExprEq, which groups equal HsExprs for the purpose of pattern-match overlap checking, I found that dictionary evidence for the same type could have two different names. Easily fixed by comparing types not names. * I did quite a bit of annoying fiddling around in GHC.Tc.Gen.Head and GHC.Tc.Gen.App to get error message locations and contexts right, esp in splitHsApps, and the HsExprArg type. Tiresome and not very illuminating. But at least the tricky, higher order, Rebuilder function is gone. * Some refactoring in GHC.Tc.Utils.Monad around contexts and locations for rebindable syntax. * Incidentally fixes #19346, because we now print renamed, rather than typechecked, syntax in error mesages about applications. The commit removes the vestigial module GHC.Builtin.RebindableNames, and thus triggers a 2.4% metric decrease for test MultiLayerModules (#19293). Metric Decrease: MultiLayerModules T12545
* Fix typosBrian Wignall2021-02-063-7/+7
|
* Introduce the DecoratedSDoc typeAlfredo Di Napoli2021-02-012-7/+7
| | | | | This commit introduces a DecoratedSDoc type which replaces the old ErrDoc, and hopefully better reflects the intent.
* Rename ErrMsg into MsgEnvelopeAlfredo Di Napoli2021-02-012-9/+9
| | | | Updates Haddock submodule
* Remove ErrDoc and MsgDocAlfredo Di Napoli2021-02-012-7/+7
| | | | | | | | | | | | | This commit boldly removes the ErrDoc and the MsgDoc from the codebase. The former was introduced with the only purpose of classifying errors according to their importance, but a similar result can be obtained just by having a simple [SDoc], and placing bullets after each of them. On top of that I have taken the perhaps controversial decision to also banish MsgDoc, as it was merely a type alias over an SDoc and as such it wasn't offering any extra type safety. Granted, it was perhaps making type signatures slightly more "focused", but at the expense of cognitive burden: if it's really just an SDoc, let's call it with its proper name.
* Make PatSyn immutableSimon Peyton Jones2021-01-291-1/+1
| | | | | | | | | | Provoked by #19074, this patch makes GHC.Core.PatSyn.PatSyn immutable, by recording only the *Name* of the matcher and builder rather than (as currently) the *Id*. See Note [Keep Ids out of PatSyn] in GHC.Core.PatSyn. Updates haddock submodule.
* Add explicit import lists to Data.List importsOleg Grenrus2021-01-293-3/+3
| | | | | | | | | | | | | Related to a future change in Data.List, https://downloads.haskell.org/ghc/8.10.3/docs/html/users_guide/using-warnings.html?highlight=wcompat#ghc-flag--Wcompat-unqualified-imports Companion pull&merge requests: - https://github.com/judah/haskeline/pull/153 - https://github.com/haskell/containers/pull/762 - https://gitlab.haskell.org/ghc/packages/hpc/-/merge_requests/9 After these the actual change in Data.List should be easy to do.
* Separate AST from GhcPass (#18936)John Ericson2021-01-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ---------------- What: There are two splits. The first spit is: - `Language.Haskell.Syntax.Extension` - `GHC.Hs.Extension` where the former now just contains helpers like `NoExtCon` and all the families, and the latter is everything having to do with `GhcPass`. The second split is: - `Language.Haskell.Syntax.<mod>` - `GHC.Hs.<mod>` Where the former contains all the data definitions, and the few helpers that don't use `GhcPass`, and the latter contains everything else. The second modules also reexport the former. ---------------- Why: See the issue for more details, but in short answer is we're trying to grasp at the modularity TTG is supposed to offer, after a long time of mainly just getting the safety benefits of more complete pattern matching on the AST. Now, we have an AST datatype which, without `GhcPass` is decently stripped of GHC-specific concerns. Whereas before, not was it GHC-specific, it was aware of all the GHC phases despite the parameterization, with the instances and parametric data structure side-by-side. For what it's worth there are also some smaller, imminent benefits: - The latter change also splits a strongly connected component in two, since none of the `Language.Haskell.Syntax.*` modules import the older ones. - A few TTG violations (Using GhcPass directly in the AST) in `Expr` are now more explicitly accounted for with new type families to provide the necessary indirection. ----------------- Future work: - I don't see why all the type families should live in `Language.Haskell.Syntax.Extension`. That seems anti-modular for little benefit. All the ones used just once can be moved next to the AST type they serve as an extension point for. - Decide what to do with the `Outputable` instances. Some of these are no orphans because they referred to `GhcPass`, and had to be moved. I think the types could be generalized so they don't refer to `GhcPass` and therefore can be moved back, but having gotten flak for increasing the size and complexity types when generalizing before, I did *not* want to do this. - We should triage the remaining contents of `GHC.Hs.<mod>`. The renaming helpers are somewhat odd for needing `GhcPass`. We might consider if they are a) in fact only needed by one phase b) can be generalized to be non-GhcPass-specific (e.g. take a callback rather than GADT-match with `IsPass`) and then they can live in `Language.Haskell.Syntax.<mod>`. For more details, see https://gitlab.haskell.org/ghc/ghc/-/wikis/implementing-trees-that-grow Bumps Haddock submodule
* Parameterise Messages over eAlfredo Di Napoli2021-01-222-10/+10
| | | | | | | | | This commit paves the way to a richer and more structured representation of GHC error messages, as per GHC proposal #306. More specifically 'Messages' from 'GHC.Types.Error' now gains an extra type parameter, that we instantiate to 'ErrDoc' for now. Later, this will allow us to replace ErrDoc with something more structure (for example messages coming from the parser, the typechecker etc).
* Remove unused extension pragmas from the compiler code baseHécate2021-01-171-1/+1
|
* Remove errShortString, cleanup error-related functionsAlfredo Di Napoli2021-01-092-22/+20
| | | | | | | | | | | This commit removes the errShortString field from the ErrMsg type, allowing us to cleanup a lot of dynflag-dependent error functions, and move them in a more specialised 'GHC.Driver.Errors' closer to the driver, where they are actually used. Metric Increase: T4801 T9961
* Refactor renamer datastructuresAdam Gundry2020-12-241-3/+3
| | | | | | | | | | | | | | | This patch significantly refactors key renamer datastructures (primarily Avail and GlobalRdrElt) in order to treat DuplicateRecordFields in a more robust way. In particular it allows the extension to be used with pattern synonyms (fixes where mangled record selector names could be printed instead of field labels (e.g. with -Wpartial-fields or hole fits, see new tests). The key idea is the introduction of a new type GreName for names that may represent either normal entities or field labels. This is then used in GlobalRdrElt and AvailInfo, in place of the old way of representing fields using FldParent (yuck) and an extra list in AvailTC. Updates the haddock submodule.
* Support package qualifier in Prelude importSylvain Henry2020-12-231-5/+9
| | | | Fix #19082, #17045
* Fix Haddock parse error in GHC.Parser.PostProcess.HaddockMatthew Pickering2020-12-201-2/+2
|
* Rename parser Error and Warning typesAlfredo Di Napoli2020-12-186-332/+333
| | | | | | | | | This commit renames parser's Error and Warning types (and their constructors) to have a 'Ps' prefix, so that this would play nicely when more errors and warnings for other phases of the pipeline will be added. This will make more explicit which is the particular type of error and warning we are dealing with, and will be more informative for users to see in the generated Haddock.
* Implement type applications in patternsCale Gibbard2020-12-145-29/+33
| | | | | The haddock submodule is also updated so that it understands the changes to patterns.
* Parser: move parser utils into their own moduleSylvain Henry2020-12-111-0/+58
| | | | Move code unrelated to runtime evaluation out of GHC.Runtime.Eval
* Replace HsImplicitBndrs with HsOuterTyVarBndrsRyan Scott2020-11-062-30/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This refactors the GHC AST to remove `HsImplicitBndrs` and replace it with `HsOuterTyVarBndrs`, a type which records whether the outermost quantification in a type is explicit (i.e., with an outermost, invisible `forall`) or implicit. As a result of this refactoring, it is now evident in the AST where the `forall`-or-nothing rule applies: it's all the places that use `HsOuterTyVarBndrs`. See the revamped `Note [forall-or-nothing rule]` in `GHC.Hs.Type` (previously in `GHC.Rename.HsType`). Moreover, the places where `ScopedTypeVariables` brings lexically scoped type variables into scope are a subset of the places that adhere to the `forall`-or-nothing rule, so this also makes places that interact with `ScopedTypeVariables` easier to find. See the revamped `Note [Lexically scoped type variables]` in `GHC.Hs.Type` (previously in `GHC.Tc.Gen.Sig`). `HsOuterTyVarBndrs` are used in type signatures (see `HsOuterSigTyVarBndrs`) and type family equations (see `HsOuterFamEqnTyVarBndrs`). The main difference between the former and the latter is that the former cares about specificity but the latter does not. There are a number of knock-on consequences: * There is now a dedicated `HsSigType` type, which is the combination of `HsOuterSigTyVarBndrs` and `HsType`. `LHsSigType` is now an alias for an `XRec` of `HsSigType`. * Working out the details led us to a substantial refactoring of the handling of explicit (user-written) and implicit type-variable bindings in `GHC.Tc.Gen.HsType`. Instead of a confusing family of higher order functions, we now have a local data type, `SkolemInfo`, that controls how these binders are kind-checked. It remains very fiddly, not fully satisfying. But it's better than it was. Fixes #16762. Bumps the Haddock submodule. Co-authored-by: Simon Peyton Jones <simonpj@microsoft.com> Co-authored-by: Richard Eisenberg <rae@richarde.dev> Co-authored-by: Zubin Duggal <zubin@cmi.ac.in>
* Restrict Linear arrow %1 to exactly literal 1 onlyAlan Zimmerman2020-11-031-1/+2
| | | | | | | This disallows `a %001 -> b`, and makes sure the type literal is printed from its SourceText so it is clear why. Closes #18888
* Add the proper HLint rules and remove redundant keywords from compilerHécate2020-11-012-5/+4
|
* Split HsConDecl{H98,GADT}DetailsRyan Scott2020-10-302-13/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Haskell98 and GADT constructors both use `HsConDeclDetails`, which includes `InfixCon`. But `InfixCon` is never used for GADT constructors, which results in an awkward unrepresentable state. This removes the unrepresentable state by: * Renaming the existing `HsConDeclDetails` synonym to `HsConDeclH98Details`, which emphasizes the fact that it is now only used for Haskell98-style data constructors, and * Creating a new `HsConDeclGADTDetails` data type with `PrefixConGADT` and `RecConGADT` constructors that closely resemble `PrefixCon` and `InfixCon` in `HsConDeclH98Details`. The key difference is that `HsConDeclGADTDetails` lacks any way to represent infix constructors. The rest of the patch is refactoring to accommodate the new structure of `HsConDecl{H98,GADT}Details`. Some highlights: * The `getConArgs` and `hsConDeclArgTys` functions have been removed, as there is no way to implement these functions uniformly for all `ConDecl`s. For the most part, their previous call sites now pattern match on the `ConDecl`s directly and do different things for `ConDeclH98`s and `ConDeclGADT`s. I did introduce one new function to make the transition easier: `getRecConArgs_maybe`, which extracts the arguments from a `RecCon(GADT)`. This is still possible since `RecCon(GADT)`s still use the same representation in both `HsConDeclH98Details` and `HsConDeclGADTDetails`, and since the pattern that `getRecConArgs_maybe` implements is used in several places, I thought it worthwhile to factor it out into its own function. * Previously, the `con_args` fields in `ConDeclH98` and `ConDeclGADT` were both of type `HsConDeclDetails`. Now, the former is of type `HsConDeclH98Details`, and the latter is of type `HsConDeclGADTDetails`, which are distinct types. As a result, I had to rename the `con_args` field in `ConDeclGADT` to `con_g_args` to make it typecheck. A consequence of all this is that the `con_args` field is now partial, so using `con_args` as a top-level field selector is dangerous. (Indeed, Haddock was using `con_args` at the top-level, which caused it to crash at runtime before I noticed what was wrong!) I decided to add a disclaimer in the 9.2.1 release notes to advertise this pitfall. Fixes #18844. Bumps the `haddock` submodule.
* Remove unnecessary gender from comments/docsRichard Eisenberg2020-10-291-2/+2
| | | | | | | While, say, alternating "he" and "she" in sequential writing may be nicer than always using "they", reading code/documentation is almost never sequential. If this small change makes individuals feel more welcome in GHC's codebase, that's a good thing.
* Split GHC.Driver.TypesSylvain Henry2020-10-294-14/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I was working on making DynFlags stateless (#17957), especially by storing loaded plugins into HscEnv instead of DynFlags. It turned out to be complicated because HscEnv is in GHC.Driver.Types but LoadedPlugin isn't: it is in GHC.Driver.Plugins which depends on GHC.Driver.Types. I didn't feel like introducing yet another hs-boot file to break the loop. Additionally I remember that while we introduced the module hierarchy (#13009) we talked about splitting GHC.Driver.Types because it contained various unrelated types and functions, but we never executed. I didn't feel like making GHC.Driver.Types bigger with more unrelated Plugins related types, so finally I bit the bullet and split GHC.Driver.Types. As a consequence this patch moves a lot of things. I've tried to put them into appropriate modules but nothing is set in stone. Several other things moved to avoid loops. * Removed Binary instances from GHC.Utils.Binary for random compiler things * Moved Typeable Binary instances into GHC.Utils.Binary.Typeable: they import a lot of things that users of GHC.Utils.Binary don't want to depend on. * put everything related to Units/Modules under GHC.Unit: GHC.Unit.Finder, GHC.Unit.Module.{ModGuts,ModIface,Deps,etc.} * Created several modules under GHC.Types: GHC.Types.Fixity, SourceText, etc. * Split GHC.Utils.Error (into GHC.Types.Error) * Finally removed GHC.Driver.Types Note that this patch doesn't put loaded plugins into HscEnv. It's left for another patch. Bump haddock submodule
* API Annotations: put constructors in alphabetical orderAlan Zimmerman2020-10-281-2/+2
|
* Api Annotations: Introduce AnnPercent for HsExplicitMultAlan Zimmerman2020-10-272-4/+6
| | | | | | | | For the case foo :: a %p -> b The location of the '%' is captured, separate from the 'p'
* API Annotations: Keep track of unicode for linear arrow notationwip/az/unicode-hsscaledAlan Zimmerman2020-10-203-5/+6
| | | | | | | | | | | The linear arrow can be parsed as `%1 ->` or a direct single token unicode equivalent. Make sure that this distinction is captured in the parsed AST by using IsUnicodeSyntax where it appears, and introduce a new API Annotation, AnnMult to represent its location when unicode is not used. Updated haddock submodule
* Implement -Woperator-whitespace (#18834)Vladislav Zavialov2020-10-193-24/+91
| | | | | | | | | | | | | | This patch implements two related warnings: -Woperator-whitespace-ext-conflict warns on uses of infix operators that would be parsed differently were a particular GHC extension enabled -Woperator-whitespace warns on prefix, suffix, and tight infix uses of infix operators Updates submodules: haddock, containers.
* Parser: don't require the HomeUnitIdSylvain Henry2020-10-131-13/+4
| | | | | | | The HomeUnitId is only used by the Cmm parser and this one has access to the DynFlags, so it can grab the UnitId of the HomeUnit from them. Bump haddock submodule
* Lint the compiler for extraneous LANGUAGE pragmasHécate2020-10-103-26/+20
|
* ApiAnnotations : preserve parens in GADTsAlan Zimmerman2020-10-093-40/+46
| | | | | | | | | A cleanup in 7f418acf61e accidentally discarded some parens in ConDeclGADT. Make sure these stay in the AST in a usable format. Also ensure the AnnLolly does not get lost in a GADT.
* Preserve as-parsed arrow type for HsUnrestrictedArrowAlan Zimmerman2020-10-071-9/+1
| | | | | | | | | | When linear types are disabled, HsUnrestrictedArrow is treated as HslinearArrow. Move this adjustment into the type checking phase, so that the parsed source accurately represents the source as parsed. Closes #18791
* Don't import GHC.Unit to reduce the number of dependenciesSylvain Henry2020-10-011-1/+1
|
* Less DynFlags in Header parsingSylvain Henry2020-10-013-15/+14
|
* Use ADTs for parser errors/warningsSylvain Henry2020-10-018-560/+1347
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Haskell and Cmm parsers/lexers now report errors and warnings using ADTs defined in GHC.Parser.Errors. They can be printed using functions in GHC.Parser.Errors.Ppr. Some of the errors provide hints with a separate ADT (e.g. to suggest to turn on some extension). For now, however, hints are not consistent across all messages. For example some errors contain the hints in the main message. I didn't want to change any message with this patch. I expect these changes to be discussed and implemented later. Surprisingly, this patch enhances performance. On CI (x86_64/deb9/hadrian, ghc/alloc): parsing001 -11.5% T13719 -2.7% MultiLayerModules -3.5% Naperian -3.1% Bump haddock submodule Metric Decrease: MultiLayerModules Naperian T13719 parsing001
* Make the parser module less dependent on DynFlagsSylvain Henry2020-09-293-60/+55
| | | | Bump haddock submodule
* New linear types syntax: a %p -> b (#18459)Vladislav Zavialov2020-09-293-7/+12
| | | | | | Implements GHC Proposal #356 Updates the haddock submodule.
* Implement Quick Look impredicativitySimon Peyton Jones2020-09-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch implements Quick Look impredicativity (#18126), sticking very closely to the design in A quick look at impredicativity, Serrano et al, ICFP 2020 The main change is that a big chunk of GHC.Tc.Gen.Expr has been extracted to two new modules GHC.Tc.Gen.App GHC.Tc.Gen.Head which deal with typechecking n-ary applications, and the head of such applications, respectively. Both contain a good deal of documentation. Three other loosely-related changes are in this patch: * I implemented (partly by accident) points (2,3)) of the accepted GHC proposal "Clean up printing of foralls", namely https://github.com/ghc-proposals/ghc-proposals/blob/ master/proposals/0179-printing-foralls.rst (see #16320). In particular, see Note [TcRnExprMode] in GHC.Tc.Module - :type instantiates /inferred/, but not /specified/, quantifiers - :type +d instantiates /all/ quantifiers - :type +v is killed off That completes the implementation of the proposal, since point (1) was done in commit df08468113ab46832b7ac0a7311b608d1b418c4d Author: Krzysztof Gogolewski <krzysztof.gogolewski@tweag.io> Date: Mon Feb 3 21:17:11 2020 +0100 Always display inferred variables using braces * HsRecFld (which the renamer introduces for record field selectors), is now preserved by the typechecker, rather than being rewritten back to HsVar. This is more uniform, and turned out to be more convenient in the new scheme of things. * The GHCi debugger uses a non-standard unification that allows the unification variables to unify with polytypes. We used to hack this by using ImpredicativeTypes, but that doesn't work anymore so I introduces RuntimeUnkTv. See Note [RuntimeUnkTv] in GHC.Runtime.Heap.Inspect Updates haddock submodule. WARNING: this patch won't validate on its own. It was too hard to fully disentangle it from the following patch, on type errors and kind generalisation. Changes to tests * Fixes #9730 (test added) * Fixes #7026 (test added) * Fixes most of #8808, except function `g2'` which uses a section (which doesn't play with QL yet -- see #18126) Test added * Fixes #1330. NB Church1.hs subsumes Church2.hs, which is now deleted * Fixes #17332 (test added) * Fixes #4295 * This patch makes typecheck/should_run/T7861 fail. But that turns out to be a pre-existing bug: #18467. So I have just made T7861 into expect_broken(18467)
* Introduce and use DerivClauseTys (#18662)Ryan Scott2020-09-151-3/+22
| | | | | | | | | | | | This switches `deriv_clause_tys` so that instead of using a list of `LHsSigType`s to represent the types in a `deriving` clause, it now uses a sum type. `DctSingle` represents a `deriving` clause with no enclosing parentheses, while `DctMulti` represents a clause with enclosing parentheses. This makes pretty-printing easier and avoids confusion between `HsParTy` and the enclosing parentheses in `deriving` clauses, which are different semantically. Fixes #18662.
* Remove GENERATED pragma, as it is not being usedAlan Zimmerman2020-09-091-2/+0
| | | | | | | | | | | | | | | | | | | | | @alanz pointed out on ghc-devs that the payload of this pragma does not appear to be used anywhere. I (@bgamari) did some digging and traced the pragma's addition back to d386e0d2 (way back in 2006!). It appears that it was intended to be used by code generators for use in informing the code coveraging checker about generated code provenance. When it was added it used the pragma's "payload" fields as source location information to build an "ExternalBox". However, it looks like this was dropped a year later in 55a5d8d9. At this point it seems like the pragma serves no useful purpose. Given that it also is not documented, I think we should remove it. Updates haddock submodule Closes #18639
* Add HomeUnit typeSylvain Henry2020-08-131-2/+4
| | | | | | | | | | | | | | | | | | | | | | | Since Backpack the "home unit" is much more involved than what it was before (just an identifier obtained with `-this-unit-id`). Now it is used in conjunction with `-component-id` and `-instantiated-with` to configure module instantiations and to detect if we are type-checking an indefinite unit or compiling a definite one. This patch introduces a new HomeUnit datatype which is much easier to understand. Moreover to make GHC support several packages in the same instances, we will need to handle several HomeUnits so having a dedicated (documented) type is helpful. Finally in #14335 we will also need to handle the case where we have no HomeUnit at all because we are only loading existing interfaces for plugins which live in a different space compared to units used to produce target code. Several functions will have to be refactored to accept "Maybe HomeUnit" parameters instead of implicitly querying the HomeUnit fields in DynFlags. Having a dedicated type will make this easier. Bump haddock submodule
* parser: Suggest ImportQualifiedPost in prepositive import warningBen Gamari2020-08-131-0/+1
| | | | As suggested in #18545.
* DynFlags: disentangle OutputableSylvain Henry2020-08-124-5/+5
| | | | | | | | | - put panic related functions into GHC.Utils.Panic - put trace related functions using DynFlags in GHC.Driver.Ppr One step closer making Outputable fully independent of DynFlags. Bump haddock submodule
* Api Annotations : Adjust SrcSpans for prefix bang (!).Alan Zimmerman2020-08-091-2/+3
| | | | | | And prefix ~ (cherry picked from commit 8dbee2c578b1f642d45561be3f416119863e01eb)
* ApiAnnotations; tweaks for ghc-exactprint updateAlan Zimmerman2020-08-071-2/+3
| | | | | | Remove unused ApiAnns, add one for linear arrow. Include API Annotations for trailing comma in export list.
* Clean up the story around runPV/runECP_P/runECP_PVVladislav Zavialov2020-08-061-41/+36
| | | | | | | | | | | | | This patch started as a small documentation change, an attempt to make Note [Parser-Validator] and Note [Ambiguous syntactic categories] more clear and up-to-date. But it turned out that runECP_P/runECP_PV are weakly motivated, and it's easier to remove them than to find a good rationale/explanation for their existence. As the result, there's a bit of refactoring in addition to a documentation update.
* Grammar for types and data/newtype constructorsVladislav Zavialov2020-08-061-339/+166
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before this patch, we parsed types into a reversed sequence of operators and operands. For example, (F x y + G a b * X) would be parsed as [X, *, b, a, G, +, y, x, F], using a simple grammar: tyapps : tyapp | tyapps tyapp tyapp : atype | PREFIX_AT atype | tyop | unpackedness Then we used a hand-written state machine to assemble this either into a type, using 'mergeOps', or into a constructor, using 'mergeDataCon'. This is due to a syntactic ambiguity: data T1 a = MkT1 a data T2 a = Ord a => MkT2 a In T1, what follows after the = sign is a data/newtype constructor declaration. However, in T2, what follows is a type (of kind Constraint). We don't know which of the two we are parsing until we encounter =>, and we cannot check for => without unlimited lookahead. This poses a few issues when it comes to e.g. infix operators: data I1 = Int :+ Bool :+ Char -- bad data I2 = Int :+ Bool :+ Char => MkI2 -- fine By this issue alone we are forced into parsing into an intermediate representation and doing a separate validation pass. However, should that intermediate representation be as low-level as a flat sequence of operators and operands? Before GHC Proposal #229, the answer was Yes, due to some particularly nasty corner cases: data T = ! A :+ ! B -- used to be fine, hard to parse data T = ! A :+ ! B => MkT -- bad However, now the answer is No, as this corner case is gone: data T = ! A :+ ! B -- bad data T = ! A :+ ! B => MkT -- bad This means we can write a proper grammar for types, overloading it in the DisambECP style, see Note [Ambiguous syntactic categories]. With this patch, we introduce a new class, DisambTD. Just like DisambECP is used to disambiguate between expressions, commands, and patterns, DisambTD is used to disambiguate between types and data/newtype constructors. This way, we get a proper, declarative grammar for constructors and types: infixtype : ftype | ftype tyop infixtype | unpackedness infixtype ftype : atype | tyop | ftype tyarg | ftype PREFIX_AT tyarg tyarg : atype | unpackedness atype And having a grammar for types means we are a step closer to using a single grammar for types and expressions.
* Remove ConDeclGADTPrefixPsRyan Scott2020-08-022-34/+32
| | | | | | | | | | | | | | | | This removes the `ConDeclGADTPrefixPs` per the discussion in #18517. Most of this patch simply removes code, although the code in the `rnConDecl` case for `ConDeclGADTPrefixPs` had to be moved around a bit: * The nested `forall`s check now lives in the `rnConDecl` case for `ConDeclGADT`. * The `LinearTypes`-specific code that used to live in the `rnConDecl` case for `ConDeclGADTPrefixPs` now lives in `GHC.Parser.PostProcess.mkGadtDecl`, which is now monadic so that it can check if `-XLinearTypes` is enabled. Fixes #18157.
View Lorry Controller Status