summaryrefslogtreecommitdiff
path: root/compiler/hsSyn
Commit message (Collapse)AuthorAgeFilesLines
...
* Refactor in TcMatchesSimon Peyton Jones2016-03-312-9/+10
| | | | | | | | | | * Move the several calls of tauifyMultipleMatches into tcMatches, so that it can be called only once, and the invariants are clearer * I discovered in doing this that HsLamCase had a redundant and tiresome argument, so I removed it. That in turn allowed some modest but nice code simplification
* Show: Restore redundant parentheses around recordsBen Gamari2016-03-241-4/+2
| | | | | | | | | | | | | | | | | | | | As discussed in #2530 we are going to continue to produce parentheses here in order to preserve compatibility with previous GHC releases. It was found that dropped parentheses would break some testsuites which compared against output from Show. This has been documented in the users guide. This reverts commit 5692643c9d17e746327588cd6157a923642b7975. Test Plan: Validate Reviewers: hvr, austin Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D2027 GHC Trac Issues: #2350
* Fix #11711.Richard Eisenberg2016-03-171-3/+5
| | | | | | | | There were two bugs here, both simple: we need to filter out covars before calling isMetaTyVar in the solver, and TcPat had a tcSubType the wrong way round. test case: dependent/should_compile/T11711
* Fix #11648.Richard Eisenberg2016-03-143-13/+28
| | | | | | | | | | | | We now check that a CUSK is really a CUSK and issue an error if it isn't. This also involves more solving and zonking in kcHsTyVarBndrs, which was the outright bug reported in #11648. Test cases: polykinds/T11648{,b} This updates the haddock submodule. [skip ci]
* Refactor visible type application.Richard Eisenberg2016-03-142-42/+47
| | | | | | | | | | | | | This replaces the old HsType and HsTypeOut constructors with HsAppType and HsAppTypeOut, leading to some simplification. (This refactoring addresses #11329.) This also fixes #11456, which stumbled over HsType (which is not an expression). test case: ghci/scripts/T11456 [skip ci]
* Fix printing of an `IfacePatSyn`Rik Steenkamp2016-03-051-12/+0
| | | | | | | | | | | | | | | | | Now the existentially quantified type variables are printed at the correct location when printing a pattern synonym type from an `IfacePatSyn`. The function `pprIfaceContextMaybe` has been removed as it is no longer needed. Fixes #11524. Reviewers: austin, goldfire, thomie, bgamari, mpickering Reviewed By: bgamari Differential Revision: https://phabricator.haskell.org/D1958 GHC Trac Issues: #11524
* Reconstruct record expression in bidir pattern synonymMatthew Pickering2016-02-251-3/+6
| | | | | | | | | | Reviewers: austin, rdragon, bgamari Reviewed By: bgamari Subscribers: rdragon, thomie Differential Revision: https://phabricator.haskell.org/D1949
* Fix typosRik Steenkamp2016-02-161-1/+1
| | | | | | | | | | Reviewers: bgamari, austin Reviewed By: austin Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D1915
* Improve pretty-printing of HsWrappersSimon Peyton Jones2016-02-122-26/+36
| | | | | | | | Reduces un-neede parens. Also -fprint-typechecker-elaboration now makes type applications and casts in expressions also appear. (Previously those were confusingly controlled by -fprint-explicit-coercions.)
* Simplify AbsBinds wrappingSimon Peyton Jones2016-02-121-32/+6
| | | | | | | | | | | | | | | | | | | | | | In poking Trac #11414 I found myself sinking into the abe_inst_wrap swamp. What is this strange thing? (It turned out that #11414 was breaking because of it.) Thrillingly, I found a way to sweep it away again, putting the deep instantation into tcMonoBinds instead of mkExport; and it turned out that the fun_co_fn field of FunBind was already there ready to receive exactly this wrapper. Hooray. Result * Death to abe_inst_wrap * Death to mbi_orig * Death to the plumbing in tcPolyInfer that did the deep instantiation I did find that I had to re-engineer the treatment of instance type signatures (again), but the result looks more modular and robust to me. And #11414 is fixed.
* Allow foralls in instance declsSimon Peyton Jones2016-02-082-171/+195
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch finally makes it possible to have explicit foralls in an instance decl instance forall (a :: *). Eq a => Eq [a] where ... This is useful to allow kind signatures or indeed explicicit kind for-alls; see Trac #11519 I thought it would be really easy, because an instance declaration already contains an actual HsSigType, so all the syntactic baggage is there. But in fact it turned out that instance declarations were kind-checked a little differently, because the body kind of the forall is 'Constraint' rather than '*'. So I fixed that. There a slight kludge (see Note [Body kind of a HsQualTy], but it's still a significant improvement. I also did the usual other round of refactoring, improved a few error messages, tidied up comments etc. The only significant aspect of all that was * Kill mkNakedSpecSigmaTy, mkNakedPhiTy, mkNakedFunTy These function names suggest that they do something complicated, but acutally they do nothing. So I killed them. * Swap the arg order of mkNamedBinder, just so that it is convenient to say 'map (mkNamedBinder Invisible) tvs' * I had to improve isPredTy, to deal with (illegal) types like (Eq a => Eq [a]) => blah See Note [isPeredTy complications] in Type.hs Still to come: user manual documentation for the instance-decl change.
* Refactor the typechecker to use ExpTypes.Richard Eisenberg2016-01-277-56/+141
| | | | | | | | | | | | | | | | | | | | | The idea here is described in [wiki:Typechecker]. Briefly, this refactor keeps solid track of "synthesis" mode vs "checking" in GHC's bidirectional type-checking algorithm. When in synthesis mode, the expected type is just an IORef to write to. In addition, this patch does a significant reworking of RebindableSyntax, allowing much more freedom in the types of the rebindable operators. For example, we can now have `negate :: Int -> Bool` and `(>>=) :: m a -> (forall x. a x -> m b) -> m b`. The magic is in tcSyntaxOp. This addresses tickets #11397, #11452, and #11458. Tests: typecheck/should_compile/{RebindHR,RebindNegate,T11397,T11458} th/T11452
* Split off -Wunused-type-variables from -Wunused-matchesRyanGlScott2016-01-261-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Previously, `-Wunused-matches` would fire whenever it detected unused type variables in a type family or data family instance. This can be annoying for users who wish to use type variable names as documentation, as being `-Wall`-compliant would mean that they'd have to prefix many of their type variable names with underscores, making the documentation harder to read. To avoid this, a new warning `-Wunused-type-variables` was created that only encompasses unused variables in family instances. `-Wunused-matches` reverts back to its role of only warning on unused term-level pattern names. Unlike `-Wunused-matches`, `-Wunused-type-variables` is not implied by `-Wall`. Fixes #11451. Test Plan: ./validate Reviewers: goldfire, ekmett, austin, hvr, simonpj, bgamari Reviewed By: simonpj, bgamari Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D1825 GHC Trac Issues: #11451
* Replace calls to `ptext . sLit` with `text`Jan Stolarek2016-01-188-213/+210
| | | | | | | | | | | | | | | | | | | | Summary: In the past the canonical way for constructing an SDoc string literal was the composition `ptext . sLit`. But for some time now we have function `text` that does the same. Plus it has some rules that optimize its runtime behaviour. This patch takes all uses of `ptext . sLit` in the compiler and replaces them with calls to `text`. The main benefits of this patch are clener (shorter) code and less dependencies between module, because many modules now do not need to import `FastString`. I don't expect any performance benefits - we mostly use SDocs to report errors and it seems there is little to be gained here. Test Plan: ./validate Reviewers: bgamari, austin, goldfire, hvr, alanz Subscribers: goldfire, thomie, mpickering Differential Revision: https://phabricator.haskell.org/D1784
* Work SourceText in for all integer literalsAlan Zimmerman2016-01-162-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Certain syntactic elements have integers in them, such as fixity specifications, SPECIALISE pragmas and so on. The lexer will accept mult-radix literals, with arbitrary leading zeros in these. Bring in a SourceText field to each affected AST element to capture the original literal text for use with API Annotations. Affected hsSyn elements are ``` -- See note [Pragma source text] data Activation = NeverActive | AlwaysActive | ActiveBefore SourceText PhaseNum -- Active only *strictly before* this phase | ActiveAfter SourceText PhaseNum -- Active in this phase and later deriving( Eq, Data, Typeable ) -- Eq used in comparing rules in HsDecls data Fixity = Fixity SourceText Int FixityDirection -- Note [Pragma source text] deriving (Data, Typeable) ``` and ``` | HsTickPragma -- A pragma introduced tick SourceText -- Note [Pragma source text] in BasicTypes (StringLiteral,(Int,Int),(Int,Int)) -- external span for this tick ((SourceText,SourceText),(SourceText,SourceText)) -- Source text for the four integers used in the span. -- See note [Pragma source text] in BasicTypes (LHsExpr id) ``` Updates haddock submodule Test Plan: ./validate Reviewers: goldfire, bgamari, austin Reviewed By: bgamari Subscribers: thomie, mpickering Differential Revision: https://phabricator.haskell.org/D1781 GHC Trac Issues: #11430
* Fix some typosRik Steenkamp2016-01-162-5/+4
| | | | Differential Revision: https://phabricator.haskell.org/D1785
* Fix #11405.Richard Eisenberg2016-01-152-1/+29
| | | | | | | This adds a new variant of AbsBinds that is used solely for bindings with a type signature. This allows for a simpler desugaring that does not produce the bogus output that tripped up Core Lint in ticket #11405. Should make other desugarings simpler, too.
* fix -ddump-splices to parenthesize ((\x -> x) a) correctlyYuri de Wit2016-01-091-2/+4
| | | | | | | | | | | | Test Plan: ./validate Reviewers: goldfire, austin, bgamari Subscribers: goldfire, osa1, thomie Differential Revision: https://phabricator.haskell.org/D1114 GHC Trac Issues: #10603
* Change Template Haskell representation of GADTs.Jan Stolarek2016-01-061-16/+12
| | | | | | | | | | | | | | | Previous representation of GADTs in TH was not expressive enough to express possible GADT return types. See #11341 Test Plan: ./validate Reviewers: goldfire, austin, bgamari Subscribers: thomie, RyanGlScott Differential Revision: https://phabricator.haskell.org/D1738 GHC Trac Issues: #11341
* Remove some redundant definitions/constraintsHerbert Valerio Riedel2015-12-311-1/+0
| | | | | | Starting with GHC 7.10 and base-4.8, `Monad` implies `Applicative`, which allows to simplify some definitions to exploit the superclass relationship. This a first refactoring to that end.
* Drop pre-AMP compatibility CPP conditionalsHerbert Valerio Riedel2015-12-314-23/+0
| | | | | | | | | | | | Since GHC 8.1/8.2 only needs to be bootstrap-able by GHC 7.10 and GHC 8.0 (and GHC 8.2), we can now finally drop all that pre-AMP compatibility CPP-mess for good! Reviewers: austin, goldfire, bgamari Subscribers: goldfire, thomie, erikd Differential Revision: https://phabricator.haskell.org/D1724
* Update a few references to GHC 7.12Ben Gamari2015-12-291-1/+1
|
* Visible type applicationRichard Eisenberg2015-12-244-20/+85
| | | | | | | | | | | | | This re-working of the typechecker algorithm is based on the paper "Visible type application", by Richard Eisenberg, Stephanie Weirich, and Hamidhasan Ahmed, to be published at ESOP'16. This patch introduces -XTypeApplications, which allows users to say, for example `id @Int`, which has type `Int -> Int`. See the changes to the user manual for details. This patch addresses tickets #10619, #5296, #10589.
* Tidy up and comment wildcards in family instancesSimon Peyton Jones2015-12-231-21/+29
| | | | | | I found it was possible to do this a bit more nicely See Note [Family instance declaration binders] in HsDecls, and Note [Wildcards in family instances] in RnSource
* Add a pattern-syn form of PromotionErrSimon Peyton Jones2015-12-231-15/+0
| | | | | | | | | | The main change is to add PatSynPE to PromotionErr, so that when we get an ill-staged use of a pattern synonym we get a civilised error message. We were already doing this in half-baked form in tcValBinds, but this patch tidies up the impl (which previously used a hack rather than APromotionErr), and does it in tcTyClsInstDecls too.
* Comments and white spaceSimon Peyton Jones2015-12-231-1/+1
|
* Revert "Allow as-patterns in pattern synonym declarations."Simon Peyton Jones2015-12-231-32/+0
| | | | | | | | | | I'm reverting this until we agree a design. See comment:5 in Trac #9793. Incidentally the reference to Trac #9739 in the reverted patch is bogus; it shold have said #9793. This reverts commit 44640af7afa1a01ff2e2357f7c1436b4804866fc.
* Refactor named wildcards (again)Simon Peyton Jones2015-12-222-40/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | Michal's work on #10982, #11098, refactored the handling of named wildcards by making them more like ordinary type variables. This patch takes the same idea to its logical conclusion, resulting in a much tidier, tighter implementation. Read Note [The wildcard story for types] in HsTypes. Changes: * Named wildcards are ordinary type variables, throughout * HsType no longer has a data constructor for named wildcards (was NamedWildCard in HsWildCardInfo). Named wildcards are simply HsTyVars * Similarly named wildcards disappear from Template Haskell * I refactored RnTypes to avoid polluting LocalRdrEnv with something as narrow as named wildcards. Instead the named wildcard set is carried in RnTyKiEnv. There is a submodule update for Haddock.
* Fix typechecking for pattern synonym signaturesSimon Peyton Jones2015-12-221-7/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Various tickets have revealed bad shortcomings in the typechecking of pattern type synonyms. Discussed a lot in (the latter part of) Trac #11224. This patch fixes the most complex issues: - Both parser and renamer now treat pattern synonyms as an ordinary LHsSigType. Nothing special. Hooray. - tcPatSynSig (now in TcPatSyn) typechecks the signature, and decomposes it into its pieces. See Note [Pattern synonym signatures] - tcCheckPatSyn has had a lot of refactoring. See Note [Checking against a pattern signature] The result is a lot tidier and more comprehensible. Plus, it actually works! NB: this patch doesn't actually address the precise target of #11224, namely "inlining pattern synonym does not preserve semantics". That's an unrelated bug, with a separate patch. ToDo: better documentation in the user manual Test Plan: Validate Reviewers: austin, hvr, goldfire Subscribers: goldfire, mpickering, thomie, simonpj Differential Revision: https://phabricator.haskell.org/D1685 GHC Trac Issues: #11224
* Rework Template Haskell's handling of strictnessRyanGlScott2015-12-221-8/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, Template Haskell's treatment of strictness is not enough to cover all possible combinations of unpackedness and strictness. In addition, it isn't equipped to deal with new features (such as `-XStrictData`) which can change a datatype's fields' strictness during compilation. To address this, I replaced TH's `Strict` datatype with `SourceUnpackedness` and `SourceStrictness` (which give the programmer a more complete toolkit to configure a datatype field's strictness than just `IsStrict`, `IsLazy`, and `Unpack`). I also added the ability to reify a constructor fields' strictness post-compilation through the `reifyConStrictness` function. Fixes #10697. Test Plan: ./validate Reviewers: simonpj, goldfire, bgamari, austin Reviewed By: goldfire, bgamari Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D1603 GHC Trac Issues: #10697
* Make HsAppsType contents LocatedAlan Zimmerman2015-12-223-17/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | An HsAppInfix can carry a qconop/varop preceded by a SIMPLEQUOTE as a Located RdrName. In this case AnnSimpleQuote is attached to the Located HsAppType. | SIMPLEQUOTE qconop {% ams (sLL $1 $> $ HsAppInfix $2) [mj AnnSimpleQuote $1] } | SIMPLEQUOTE varop {% ams (sLL $1 $> $ HsAppInfix $2) [mj AnnSimpleQuote $1] } This patch changes data HsType name ... | HsAppsTy [HsAppType name] to data HsType name ... | HsAppsTy [LHsAppType name] so that the annotation is not discarded when it reaches the ParsedSource
* Add proper GADTs support to Template HaskellJan Stolarek2015-12-214-51/+131
| | | | | | | | | | | | | | | | Until now GADTs were supported in Template Haskell by encoding them using normal data types. This patch adds proper support for representing GADTs in TH. Test Plan: T10828 Reviewers: goldfire, austin, bgamari Subscribers: thomie, mpickering Differential Revision: https://phabricator.haskell.org/D1465 GHC Trac Issues: #10828
* Warn about unused type variables in type familiesMichał Sośnicki2015-12-211-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The warnings are enabled with the flag -fwarn-unused-matches, the same one that enables warnings on the term level. Identifiers starting with an underscore are now always parsed as type variables. When the NamedWildCards extension is enabled, the renamer replaces those variables with named wildcards. An additional NameSet nwcs is added to LocalRdrEnv. It's used to keep names of the type variables that should be replaced with wildcards. While renaming HsForAllTy, when a name is explicitly bound it is removed from the nwcs NameSet. As a result, the renamer doesn't replace them in the quantifier body. (Trac #11098) Fixes #10982, #11098 Reviewers: alanz, bgamari, hvr, austin, jstolarek Reviewed By: jstolarek Subscribers: goldfire, mpickering, RyanGlScott, thomie Differential Revision: https://phabricator.haskell.org/D1576 GHC Trac Issues: #10982
* Add Location to RdrName in FieldOccAlan Zimmerman2015-12-213-17/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Post #11019, there have been some new instances of RdrName that are not located, in particular ```#!hs data FieldOcc name = FieldOcc { rdrNameFieldOcc :: RdrName , selectorFieldOcc :: PostRn name name } data AmbiguousFieldOcc name = Unambiguous RdrName (PostRn name name) | Ambiguous RdrName (PostTc name name) deriving (Typeable) ``` Add locations to them Updates haddock submodule to match Test Plan: ./validate Reviewers: goldfire, hvr, bgamari, austin Reviewed By: hvr Subscribers: hvr, thomie, mpickering Differential Revision: https://phabricator.haskell.org/D1670 GHC Trac Issues: #11258
* Allow as-patterns in pattern synonym declarations.Matthew Pickering2015-12-201-0/+32
| | | | | | | | | | | | | | | | | | | | | We can allow them if they contain no free variables. This patch just allows them in one direction and not to be used as builders as the original ticket suggests. Test Plan: ./validate Reviewers: austin, bgamari Reviewed By: bgamari Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D1666 GHC Trac Issues:  #9739 Conflicts: testsuite/tests/patsyn/should_fail/all.T
* Add -fprint-typechecker-elaboration flag (fixes #10662)Eugene Akentyev2015-12-171-7/+15
| | | | | | | | | | | | Reviewers: thomie, austin, bgamari Reviewed By: thomie, bgamari Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D1625 GHC Trac Issues: #10662
* Update haddock submoduleBen Gamari2015-12-161-6/+0
| | | | | | Also rename and move the horribly named isVanillaLSig to Haddock as isUserLSig, reflecting the fact that it returns whether the signature was provided by the user or generated.
* Use Cxt for deriving clauses in TH (#10819)Ben Gamari2015-12-141-7/+5
| | | | | | | | | | | | | | | | | | | | | | | Summary: Deriving clauses in the TH representations of data, newtype, data instance, and newtype instance declarations previously were just [Name], which didn't allow for more complex derived classes, eg. multi-parameter typeclasses. This switches out [Name] for Cxt, representing the derived classes as types instead of names. Test Plan: validate Reviewers: goldfire, spinda, austin Reviewed By: goldfire, austin Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D1202 GHC Trac Issues: #10819
* Refactor type families in Template HaskellJohn Leo2015-12-121-10/+19
| | | | | | | | | | | | | | | | Fixes #10902. Test Plan: validate Reviewers: goldfire, austin, hvr, jstolarek, bgamari Reviewed By: jstolarek, bgamari Subscribers: hvr, thomie Differential Revision: https://phabricator.haskell.org/D1570 GHC Trac Issues: #10902
* Implement -fwarn-missing-pat-syn-sigsMatthew Pickering2015-12-121-2/+11
| | | | | | | | | | | | | | | | | | | | | | | This adds a warning when a pattern synonym is not accompanied by a signature in the style of `-fwarn-missing-sigs`. It is turned on by -Wall. If the user specifies, `-fwarn-missing-exported-signatures` with `-fwarn-missing-pat-syn-sigs` then it will only warn when the pattern synonym is exported. Test Plan: ./validate Reviewers: hvr, austin, bgamari Reviewed By: bgamari Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D1596 GHC Trac Issues: #11053
* Add kind equalities to GHC.Richard Eisenberg2015-12-116-223/+254
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This implements the ideas originally put forward in "System FC with Explicit Kind Equality" (ICFP'13). There are several noteworthy changes with this patch: * We now have casts in types. These change the kind of a type. See new constructor `CastTy`. * All types and all constructors can be promoted. This includes GADT constructors. GADT pattern matches take place in type family equations. In Core, types can now be applied to coercions via the `CoercionTy` constructor. * Coercions can now be heterogeneous, relating types of different kinds. A coercion proving `t1 :: k1 ~ t2 :: k2` proves both that `t1` and `t2` are the same and also that `k1` and `k2` are the same. * The `Coercion` type has been significantly enhanced. The documentation in `docs/core-spec/core-spec.pdf` reflects the new reality. * The type of `*` is now `*`. No more `BOX`. * Users can write explicit kind variables in their code, anywhere they can write type variables. For backward compatibility, automatic inference of kind-variable binding is still permitted. * The new extension `TypeInType` turns on the new user-facing features. * Type families and synonyms are now promoted to kinds. This causes trouble with parsing `*`, leading to the somewhat awkward new `HsAppsTy` constructor for `HsType`. This is dispatched with in the renamer, where the kind `*` can be told apart from a type-level multiplication operator. Without `-XTypeInType` the old behavior persists. With `-XTypeInType`, you need to import `Data.Kind` to get `*`, also known as `Type`. * The kind-checking algorithms in TcHsType have been significantly rewritten to allow for enhanced kinds. * The new features are still quite experimental and may be in flux. * TODO: Several open tickets: #11195, #11196, #11197, #11198, #11203. * TODO: Update user manual. Tickets addressed: #9017, #9173, #7961, #10524, #8566, #11142. Updates Haddock submodule.
* Fix infix record field fixity (#11167 and #11173).Adam Gundry2015-12-112-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This extends D1585 with proper support for infix duplicate record fields. In particular, it is now possible to declare record fields as infix in a module for which `DuplicateRecordFields` is enabled, fixity is looked up correctly and a readable (although unpleasant) error message is generated if multiple fields with different fixities are in scope. As a bonus, `DEPRECATED` and `WARNING` pragmas now work for duplicate record fields. The pragma applies to all fields with the given label. In addition, a couple of minor `DuplicateRecordFields` bugs, which were pinpointed by the `T11167_ambig` test case, are fixed by this patch: - Ambiguous infix fields can now be disambiguated by putting a type signature on the first argument - Polymorphic type constructor signatures (such as `ContT () IO a` in `T11167_ambig`) now work for disambiguation Parts of this patch are from D1585 authored by @KaneTW. Test Plan: New tests added. Reviewers: KaneTW, bgamari, austin Reviewed By: bgamari Subscribers: thomie, hvr Differential Revision: https://phabricator.haskell.org/D1600 GHC Trac Issues: #11167, #11173
* More typos in comments/docsGabor Greif2015-12-091-1/+1
|
* An assortment of typosGabor Greif2015-12-081-3/+3
|
* Comments about polymorphic recursionSimon Peyton Jones2015-12-081-8/+46
| | | | See Trac #11176
* Refactor ConDeclAlan Zimmerman2015-12-075-103/+102
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ConDecl type in HsDecls is an uneasy compromise. For the most part, HsSyn directly reflects the syntax written by the programmer; and that gives just the right "pegs" on which to hang Alan's API annotations. But ConDecl doesn't properly reflect the syntax of Haskell-98 and GADT-style data type declarations. To be concrete, here's a draft new data type ```lang=hs data ConDecl name | ConDeclGADT { con_names :: [Located name] , con_type :: LHsSigType name -- The type after the ‘::’ , con_doc :: Maybe LHsDocString } | ConDeclH98 { con_name :: Located name , con_qvars :: Maybe (LHsQTyVars name) -- User-written forall (if any), and its implicit -- kind variables -- Non-Nothing needs -XExistentialQuantification , con_cxt :: Maybe (LHsContext name) -- ^ User-written context (if any) , con_details :: HsConDeclDetails name -- ^ Arguments , con_doc :: Maybe LHsDocString -- ^ A possible Haddock comment. } deriving (Typeable) ``` Note that For GADTs, just keep a type. That's what the user writes. NB:HsType can represent records on the LHS of an arrow: { x:Int,y:Bool} -> T con_qvars and con_cxt are both Maybe because they are both optional (the forall and the context of an existential data type For ConDeclGADT the type variables of the data type do not scope over the con_type; whereas for ConDeclH98 they do scope over con_cxt and con_details. Updates haddock submodule. Test Plan: ./validate Reviewers: simonpj, erikd, hvr, goldfire, austin, bgamari Subscribers: erikd, goldfire, thomie, mpickering Differential Revision: https://phabricator.haskell.org/D1558 GHC Trac Issues: #11028
* Major Overhaul of Pattern Match Checking (Fixes #595)George Karachalias2015-12-032-1/+62
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adresses several problems concerned with exhaustiveness and redundancy checking of pattern matching. The list of improvements includes: * Making the check type-aware (handles GADTs, Type Families, DataKinds, etc.). This fixes #4139, #3927, #8970 and other related tickets. * Making the check laziness-aware. Cases that are overlapped but affect evaluation are issued now with "Patterns have inaccessible right hand side". Additionally, "Patterns are overlapped" is now replaced by "Patterns are redundant". * Improved messages for literals. This addresses tickets #5724, #2204, etc. * Improved reasoning concerning cases where simple and overloaded patterns are matched (See #322). * Substantially improved reasoning for pattern guards. Addresses #3078. * OverloadedLists extension does not break exhaustiveness checking anymore (addresses #9951). Note that in general this cannot be handled but if we know that an argument has type '[a]', we treat it as a list since, the instance of 'IsList' gives the identity for both 'fromList' and 'toList'. If the type is not clear or is not the list type, then the check cannot do much still. I am a bit concerned about OverlappingInstances though, since one may override the '[a]' instance with e.g. an '[Int]' instance that is not the identity. * Improved reasoning for nested pattern matching (partial solution). Now we propagate type and (some) term constraints deeper when checking, so we can detect more inconsistencies. For example, this is needed for #4139. I am still not satisfied with several things but I would like to address at least the following before the next release: Term constraints are too many and not printed for non-exhaustive matches (with the exception of literals). This sometimes results in two identical (in appearance) uncovered warnings. Unless we actually show their difference, I would like to have a single warning.
* Comments only (isIrrefutablePat)Simon Peyton Jones2015-12-021-2/+6
|
* Refactor treatment of wildcardsSimon Peyton Jones2015-12-018-403/+560
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch began as a modest refactoring of HsType and friends, to clarify and tidy up exactly where quantification takes place in types. Although initially driven by making the implementation of wildcards more tidy (and fixing a number of bugs), I gradually got drawn into a pretty big process, which I've been doing on and off for quite a long time. There is one compiler performance regression as a result of all this, in perf/compiler/T3064. I still need to look into that. * The principal driving change is described in Note [HsType binders] in HsType. Well worth reading! * Those data type changes drive almost everything else. In particular we now statically know where (a) implicit quantification only (LHsSigType), e.g. in instance declaratios and SPECIALISE signatures (b) implicit quantification and wildcards (LHsSigWcType) can appear, e.g. in function type signatures * As part of this change, HsForAllTy is (a) simplified (no wildcards) and (b) split into HsForAllTy and HsQualTy. The two contructors appear when and only when the correponding user-level construct appears. Again see Note [HsType binders]. HsExplicitFlag disappears altogether. * Other simplifications - ExprWithTySig no longer needs an ExprWithTySigOut variant - TypeSig no longer needs a PostRn name [name] field for wildcards - PatSynSig records a LHsSigType rather than the decomposed pieces - The mysterious 'GenericSig' is now 'ClassOpSig' * Renamed LHsTyVarBndrs to LHsQTyVars * There are some uninteresting knock-on changes in Haddock, because of the HsSyn changes I also did a bunch of loosely-related changes: * We already had type synonyms CoercionN/CoercionR for nominal and representational coercions. I've added similar treatment for TcCoercionN/TcCoercionR mkWpCastN/mkWpCastN All just type synonyms but jolly useful. * I record-ised ForeignImport and ForeignExport * I improved the (poor) fix to Trac #10896, by making TcTyClsDecls.checkValidTyCl recover from errors, but adding a harmless, abstract TyCon to the envt if so. * I did some significant refactoring in RnEnv.lookupSubBndrOcc, for reasons that I have (embarrassingly) now totally forgotten. It had to do with something to do with import and export Updates haddock submodule.
* Implement warnings for Semigroups as parent of MonoidDavid Luposchainsky2015-11-291-0/+10
| | | | | | | | | | | | | | | | | | | | | This patch is similar to the AMP patch (#8004), which offered two functions: 1. Warn when an instance of a class has been given, but the type does not have a certain superclass instance 2. Warn when top-level definitions conflict with future Prelude names These warnings are issued as part of the new `-Wcompat` warning group. Reviewers: hvr, ekmett, austin, bgamari Reviewed By: hvr, ekmett, bgamari Subscribers: ekmett, thomie Differential Revision: https://phabricator.haskell.org/D1539 GHC Trac Issues: #11139
View Lorry Controller Status