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* compiler: de-lhs deSugar/Austin Seipp2014-12-031-289/+0
| | | | Signed-off-by: Austin Seipp <austin@well-typed.com>
* AST changes to prepare for API annotations, for #9628Alan Zimmerman2014-11-211-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | Summary: AST changes to prepare for API annotations Add locations to parts of the AST so that API annotations can then be added. The outline of the whole process is captured here https://ghc.haskell.org/trac/ghc/wiki/GhcAstAnnotations This change updates the haddock submodule. Test Plan: sh ./validate Reviewers: austin, simonpj, Mikolaj Reviewed By: simonpj, Mikolaj Subscribers: thomie, goldfire, carter Differential Revision: https://phabricator.haskell.org/D426 GHC Trac Issues: #9628
* De-tabify and remove trailing whitespaceSimon Peyton Jones2014-09-261-65/+59
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* Make the matcher and wrapper Ids in PatSyn into LocalIds, not GlobalIdsSimon Peyton Jones2014-06-061-1/+1
| | | | | | | | | | | | | | | | | | | | This was a serious bug, exposed by Trac #9175. The matcher and wrapper must be LocalIds, like record selectors and dictionary functions, for the reasons now documented in Note [Exported LocalIds] in Id.lhs In fixing this I found - PatSyn should have an Id inside it (apart from the wrapper and matcher) It should be a Name. Hence psId --> psName, with knock-on consequences - Tidying of PatSyns in TidyPgm was wrong - The keep-alive set in Desugar.deSugar (now) doesn't need pattern synonyms in it I also cleaned up the interface to PatSyn a little, so there's a tiny knock-on effect in Haddock; hence the haddock submodule update. It's very hard to make a test for this bug, so I haven't.
* Fix egregious instantiation bug in matchOneConLike (fixing Trac #9023)Simon Peyton Jones2014-06-051-18/+15
| | | | | | | | | | | | | | | We simply weren't giving anything like the right instantiating types to patSynInstArgTys in matchOneConLike. To get these instantiating types would have involved matching the result type of the pattern synonym with the pattern type, which is tiresome. So instead I changed ConPatOut so that instead of recording the type of the *whole* pattern (in old field pat_ty), it not records the *instantiating* types (in new field pat_arg_tys). Then we canuse TcHsSyn.conLikeResTy to get the pattern type when needed. There are lots of knock-on incidental effects, but they mostly made the code simpler, so I'm happy.
* Add LANGUAGE pragmas to compiler/ source filesHerbert Valerio Riedel2014-05-151-1/+2
| | | | | | | | | | | | | | | | | | In some cases, the layout of the LANGUAGE/OPTIONS_GHC lines has been reorganized, while following the convention, to - place `{-# LANGUAGE #-}` pragmas at the top of the source file, before any `{-# OPTIONS_GHC #-}`-lines. - Moreover, if the list of language extensions fit into a single `{-# LANGUAGE ... -#}`-line (shorter than 80 characters), keep it on one line. Otherwise split into `{-# LANGUAGE ... -#}`-lines for each individual language extension. In both cases, try to keep the enumeration alphabetically ordered. (The latter layout is preferable as it's more diff-friendly) While at it, this also replaces obsolete `{-# OPTIONS ... #-}` pragma occurences by `{-# OPTIONS_GHC ... #-}` pragmas.
* Implement pattern synonymsDr. ERDI Gergo2014-01-201-15/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch implements Pattern Synonyms (enabled by -XPatternSynonyms), allowing y ou to assign names to a pattern and abstract over it. The rundown is this: * Named patterns are introduced by the new 'pattern' keyword, and can be either *unidirectional* or *bidirectional*. A unidirectional pattern is, in the simplest sense, simply an 'alias' for a pattern, where the LHS may mention variables to occur in the RHS. A bidirectional pattern synonym occurs when a pattern may also be used in expression context. * Unidirectional patterns are declared like thus: pattern P x <- x:_ The synonym 'P' may only occur in a pattern context: foo :: [Int] -> Maybe Int foo (P x) = Just x foo _ = Nothing * Bidirectional patterns are declared like thus: pattern P x y = [x, y] Here, P may not only occur as a pattern, but also as an expression when given values for 'x' and 'y', i.e. bar :: Int -> [Int] bar x = P x 10 * Patterns can't yet have their own type signatures; signatures are inferred. * Pattern synonyms may not be recursive, c.f. type synonyms. * Pattern synonyms are also exported/imported using the 'pattern' keyword in an import/export decl, i.e. module Foo (pattern Bar) where ... Note that pattern synonyms share the namespace of constructors, so this disambiguation is required as a there may also be a 'Bar' type in scope as well as the 'Bar' pattern. * The semantics of a pattern synonym differ slightly from a typical pattern: when using a synonym, the pattern itself is matched, followed by all the arguments. This means that the strictness differs slightly: pattern P x y <- [x, y] f (P True True) = True f _ = False g [True, True] = True g _ = False In the example, while `g (False:undefined)` evaluates to False, `f (False:undefined)` results in undefined as both `x` and `y` arguments are matched to `True`. For more information, see the wiki: https://ghc.haskell.org/trac/ghc/wiki/PatternSynonyms https://ghc.haskell.org/trac/ghc/wiki/PatternSynonyms/Implementation Reviewed-by: Simon Peyton Jones <simonpj@microsoft.com> Signed-off-by: Austin Seipp <austin@well-typed.com>
* Globally replace "hackage.haskell.org" with "ghc.haskell.org"Simon Marlow2013-10-011-1/+1
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* Allow empty case expressions (and lambda-case) with -XEmptyCaseSimon Peyton Jones2013-01-041-1/+2
| | | | | | | | | | | | | | | The main changes are: * Parser accepts empty case alternatives * Renamer checks that -XEmptyCase is on in that case * (Typechecker is pretty much unchanged.) * Desugarer desugars empty case alternatives, esp: - Match.matchWrapper and Match.match now accept empty eqns - New function matchEmpty deals with the empty case - See Note [Empty case alternatives] in Match This patch contains most of the work, but it's a bit mixed up with a refactoring of MatchGroup that I did at the same time (next commit).
* Move tARGET_* out of HaskellConstantsIan Lynagh2012-09-171-2/+4
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* Change how macros like ASSERT are definedIan Lynagh2012-06-051-1/+1
| | | | | By using Haskell's debugIsOn rather than CPP's "#ifdef DEBUG", we don't need to kludge things to keep the warning checker happy etc.
* Monadify dsEvTerm in preparation for generating Integer & String evidence.Iavor S. Diatchki2012-01-071-6/+9
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* Allow full constraint solving under a for-all (Trac #5595)Simon Peyton Jones2011-12-051-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The main idea is that when we unify forall a. t1 ~ forall a. t2 we get constraints from unifying t1~t2 that mention a. We are producing a coercion witnessing the equivalence of the for-alls, and inside *that* coercion we need bindings for the solved constraints arising from t1~t2. We didn't have way to do this before. The big change is that here's a new type TcEvidence.TcCoercion, which is much like Coercion.Coercion except that there's a slot for TcEvBinds in it. This has a wave of follow-on changes. Not deep but broad. * New module TcEvidence, which now contains the HsWrapper TcEvBinds, EvTerm etc types that used to be in HsBinds * The typechecker works exclusively in terms of TcCoercion. * The desugarer converts TcCoercion to Coercion * The main payload is in TcUnify.unifySigmaTy. This is the function that had a gross hack before, but is now beautiful. * LCoercion is gone! Hooray. Many many fiddly changes in conssequence. But it's nice.
* Use -fwarn-tabs when validatingIan Lynagh2011-11-041-0/+7
| | | | | We only use it for "compiler" sources, i.e. not for libraries. Many modules have a -fno-warn-tabs kludge for now.
* Fix some warningsIan Lynagh2011-10-141-7/+4
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* Implement -XConstraintKindMax Bolingbroke2011-09-061-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Basically as documented in http://hackage.haskell.org/trac/ghc/wiki/KindFact, this patch adds a new kind Constraint such that: Show :: * -> Constraint (?x::Int) :: Constraint (Int ~ a) :: Constraint And you can write *any* type with kind Constraint to the left of (=>): even if that type is a type synonym, type variable, indexed type or so on. The following (somewhat related) changes are also made: 1. We now box equality evidence. This is required because we want to give (Int ~ a) the *lifted* kind Constraint 2. For similar reasons, implicit parameters can now only be of a lifted kind. (?x::Int#) => ty is now ruled out 3. Implicit parameter constraints are now allowed in superclasses and instance contexts (this just falls out as OK with the new constraint solver) Internally the following major changes were made: 1. There is now no PredTy in the Type data type. Instead GHC checks the kind of a type to figure out if it is a predicate 2. There is now no AClass TyThing: we represent classes as TyThings just as a ATyCon (classes had TyCons anyway) 3. What used to be (~) is now pretty-printed as (~#). The box constructor EqBox :: (a ~# b) -> (a ~ b) 4. The type LCoercion is used internally in the constraint solver and type checker to represent coercions with free variables of type (a ~ b) rather than (a ~# b)
* This BIG PATCH contains most of the work for the New Coercion RepresentationSimon Peyton Jones2011-04-191-1/+0
| | | | | | | | | | | | | | See the paper "Practical aspects of evidence based compilation in System FC" * Coercion becomes a data type, distinct from Type * Coercions become value-level things, rather than type-level things, (although the value is zero bits wide, like the State token) A consequence is that a coerion abstraction increases the arity by 1 (just like a dictionary abstraction) * There is a new constructor in CoreExpr, namely Coercion, to inject coercions into terms
* Super-monster patch implementing the new typechecker -- at lastsimonpj@microsoft.com2010-09-131-4/+2
| | | | | | | | | This major patch implements the new OutsideIn constraint solving algorithm in the typecheker, following our JFP paper "Modular type inference with local assumptions". Done with major help from Dimitrios Vytiniotis and Brent Yorgey.
* Remove unused importsIan Lynagh2009-07-071-1/+0
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* Fix Trac #246: order of matching in record patternssimonpj@microsoft.com2009-03-301-40/+112
| | | | | | | | | | | | | While I was looking at the desugaring of pattern matching (fixing Trac #3126) I finally got around to fixing another long-standing bug: when matching in a record pattern, GHC should match left-to-right in the programmer-specfied order, *not* left-to-right positionally in the original record declaration. Needless to say, that requires a little more code. See Note [Record patterns] in MatchCon.lhs
* Spelling error in commentsimonpj@microsoft.com2008-10-191-1/+1
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* Handle introduction of MkCore in MatchConMax Bolingbroke2008-07-311-1/+2
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* Don't import FastString in HsVersions.hIan Lynagh2008-03-291-2/+0
| | | | Modules that need it import it themselves instead.
* Fixed warnings in deSugar/MatchCon, except for incomplete pattern matchesTwan van Laarhoven2008-02-031-4/+11
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* Fix CodingStyle#Warnings URLsIan Lynagh2007-09-041-1/+1
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* Use OPTIONS rather than OPTIONS_GHC for pragmasIan Lynagh2007-09-031-2/+2
| | | | | | | Older GHCs can't parse OPTIONS_GHC. This also changes the URL referenced for the -w options from WorkingConventions#Warnings to CodingStyle#Warnings for the compiler modules.
* Add {-# OPTIONS_GHC -w #-} and some blurb to all compiler modulesIan Lynagh2007-09-011-0/+7
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* Add several new record featuresLemmih2007-06-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1. Record disambiguation (-fdisambiguate-record-fields) In record construction and pattern matching (although not in record updates) it is clear which field name is intended even if there are several in scope. This extension uses the constructor to disambiguate. Thus C { x=3 } uses the 'x' field from constructor C (assuming there is one) even if there are many x's in scope. 2. Record punning (-frecord-puns) In a record construction or pattern match or update you can omit the "=" part, thus C { x, y } This is just syntactic sugar for C { x=x, y=y } 3. Dot-dot notation for records (-frecord-dot-dot) In record construction or pattern match (but not update) you can use ".." to mean "all the remaining fields". So C { x=v, .. } means to fill in the remaining fields to give C { x=v, y=y } (assuming C has fields x and y). This might reasonably considered very dodgy stuff. For pattern-matching it brings into scope a bunch of things that are not explictly mentioned; and in record construction it just picks whatver 'y' is in scope for the 'y' field. Still, Lennart Augustsson really wants it, and it's a feature that is extremely easy to explain. Implementation ~~~~~~~~~~~~~~ I thought of using the "parent" field in the GlobalRdrEnv, but that's really used for import/export and just isn't right for this. For example, for import/export a field is a subordinate of the *type constructor* whereas here we need to know what fields belong to a particular *data* constructor. The main thing is that we need to map a data constructor to its fields, and we need to do so in the renamer. For imported modules it's easy: just look in the imported TypeEnv. For the module being compiled, we make a new field tcg_field_env in the TcGblEnv. The important functions are RnEnv.lookupRecordBndr RnEnv.lookupConstructorFields There is still a significant infelicity in the way the renamer works on patterns, which I'll tackle next. I also did quite a bit of refactoring in the representation of record fields (mainly in HsPat).***END OF DESCRIPTION*** Place the long patch description above the ***END OF DESCRIPTION*** marker. The first line of this file will be the patch name. This patch contains the following changes: M ./compiler/deSugar/Check.lhs -3 +5 M ./compiler/deSugar/Coverage.lhs -6 +7 M ./compiler/deSugar/DsExpr.lhs -6 +13 M ./compiler/deSugar/DsMeta.hs -8 +8 M ./compiler/deSugar/DsUtils.lhs -1 +1 M ./compiler/deSugar/MatchCon.lhs -2 +2 M ./compiler/hsSyn/Convert.lhs -3 +3 M ./compiler/hsSyn/HsDecls.lhs -9 +25 M ./compiler/hsSyn/HsExpr.lhs -13 +3 M ./compiler/hsSyn/HsPat.lhs -25 +63 M ./compiler/hsSyn/HsUtils.lhs -3 +3 M ./compiler/main/DynFlags.hs +6 M ./compiler/parser/Parser.y.pp -13 +17 M ./compiler/parser/RdrHsSyn.lhs -16 +18 M ./compiler/rename/RnBinds.lhs -2 +2 M ./compiler/rename/RnEnv.lhs -22 +82 M ./compiler/rename/RnExpr.lhs -34 +12 M ./compiler/rename/RnHsSyn.lhs -3 +2 M ./compiler/rename/RnSource.lhs -50 +78 M ./compiler/rename/RnTypes.lhs -50 +84 M ./compiler/typecheck/TcExpr.lhs -18 +18 M ./compiler/typecheck/TcHsSyn.lhs -20 +21 M ./compiler/typecheck/TcPat.lhs -8 +6 M ./compiler/typecheck/TcRnMonad.lhs -6 +15 M ./compiler/typecheck/TcRnTypes.lhs -2 +11 M ./compiler/typecheck/TcTyClsDecls.lhs -3 +4 M ./docs/users_guide/flags.xml +7 M ./docs/users_guide/glasgow_exts.xml +42
* Fix a bug in MatchCon, and clarify what dataConInstOrigArgTys doesLemmih2007-06-071-8/+12
| | | | | | | | | | | There was an outright bug in MatchCon.matchOneCon, in the construction of arg_tys. Easily fixed. It never showed up becuase the arg_tys are only used in WildPats, and they in turn seldom have their types looked (except by hsPatType). So I can't make a test case for htis. While I was investigating, I added a bit of clarifation and invariant-checking to dataConInstOrigArgTys and dataConInstArgTys
* Module header tidyup, phase 1Simon Marlow2006-10-111-11/+11
| | | | | | | | | | | | This patch is a start on removing import lists and generally tidying up the top of each module. In addition to removing import lists: - Change DATA.IOREF -> Data.IORef etc. - Change List -> Data.List etc. - Remove $Id$ - Update copyrights - Re-order imports to put non-GHC imports last - Remove some unused and duplicate imports
* Merge Haddock comment support from ghc.haddock -- big patchdavve@dtek.chalmers.se2006-10-051-2/+2
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* GADT pattern matching fixManuel M T Chakravarty2006-09-181-2/+3
| | | | | | Sun Aug 6 17:01:59 EDT 2006 Manuel M T Chakravarty <chak@cse.unsw.edu.au> * GADT pattern matching fix Wed Jul 19 10:53:09 EDT 2006 kevind@bu.edu
* Massive patch for the first months work adding System FC to GHC #9Manuel M T Chakravarty2006-08-041-60/+55
| | | | | | | | Broken up massive patch -=chak Original log message: This is (sadly) all done in one patch to avoid Darcs bugs. It's not complete work... more FC stuff to come. A compiler using just this patch will fail dismally.
* Reorganisation of the source treeSimon Marlow2006-04-071-0/+174
Most of the other users of the fptools build system have migrated to Cabal, and with the move to darcs we can now flatten the source tree without losing history, so here goes. The main change is that the ghc/ subdir is gone, and most of what it contained is now at the top level. The build system now makes no pretense at being multi-project, it is just the GHC build system. No doubt this will break many things, and there will be a period of instability while we fix the dependencies. A straightforward build should work, but I haven't yet fixed binary/source distributions. Changes to the Building Guide will follow, too.