0eb180c · rowtype-yoga/purescript-native

git.iko.soy/rowtype-yoga/purescript-native

Disallow polymorphic types in binders, prevent internalError (#2624)

* Disallow polymorphic types in binders, prevent internalError * Fix tests

commit0eb180c4f4474a5eb533ab255ffad548920ac9b6 authorPhil Freeman <paf31@cantab.net> dateSun 5 Feb 2017, 10:06 (10 years ago) parent5ff1286

5 files changed+11−8

compare with golang

unifiedsplit

examples/docs/src/ExplicitTypeSignatures.purs−2 examples/failing/2445.purs+6 src/Language/PureScript/TypeChecker/Types.hs+3−5 src/Language/PureScript/Types.hs+2 tests/TestDocs.hs−1

examples/docs/src/ExplicitTypeSignatures.purs−2

@@ -14,5 +14,3 @@ anInt = 0

1414

1515-- This should infer a type.

1616aNumber = 1.0

17−

18−foreign import nestedForAll :: forall c. (forall a b. c)

examples/failing/2445.pursnew file+6

@@ -0,0 +1,6 @@

1+-- @shouldFailWith ErrorParsingModule

2+module Main where

4+data X a = X

6+eg = \(X :: (forall a. X a)) -> X

src/Language/PureScript/TypeChecker/Types.hs+3−5

@@ -487,15 +487,12 @@ inferBinder val (NamedBinder name binder) = do

487487 return $ M.insert name val m

488488inferBinder val (PositionedBinder pos _ binder) =

489489 warnAndRethrowWithPositionTC pos $ inferBinder val binder

490−-- TODO: When adding support for polymorphic types, check subsumption here,

491−-- change the definition of `binderRequiresMonotype`,

492−-- and use `kindOfWithScopedVars`.

493490inferBinder val (TypedBinder ty binder) = do

494491 kind <- kindOf ty

495492 checkTypeKind ty kind

496− ty1 <- replaceAllTypeSynonyms <=< replaceTypeWildcards $ ty

493+ ty1 <- introduceSkolemScope <=< replaceAllTypeSynonyms <=< replaceTypeWildcards $ ty

497494 unifyTypes val ty1

498− inferBinder val binder

495+ inferBinder ty1 binder

499496inferBinder _ OpBinder{} =

500497 internalError "OpBinder should have been desugared before inferBinder"

501498inferBinder _ BinaryNoParensBinder{} =

@@ -510,6 +507,7 @@ binderRequiresMonotype NullBinder = False

510507binderRequiresMonotype (VarBinder _) = False

511508binderRequiresMonotype (NamedBinder _ b) = binderRequiresMonotype b

512509binderRequiresMonotype (PositionedBinder _ _ b) = binderRequiresMonotype b

510+binderRequiresMonotype (TypedBinder ty b) = isMonoType ty || binderRequiresMonotype b

513511binderRequiresMonotype _ = True

514512

515513-- | Instantiate polytypes only when necessitated by a binder.

src/Language/PureScript/Types.hs+2

@@ -127,6 +127,8 @@ rowFromList ((name, t):ts, r) = RCons name t (rowFromList (ts, r))

127127--

128128isMonoType :: Type -> Bool

129129isMonoType ForAll{} = False

130+isMonoType (ParensInType t) = isMonoType t

131+isMonoType (KindedType t _) = isMonoType t

130132isMonoType _ = True

131133

132134-- |

tests/TestDocs.hs−1

@@ -336,7 +336,6 @@ testCases =

336336 [ ValueShouldHaveTypeSignature (n "ExplicitTypeSignatures") "explicit" (ShowFn (hasTypeVar "something"))

337337 , ValueShouldHaveTypeSignature (n "ExplicitTypeSignatures") "anInt" (ShowFn (P.tyInt ==))

338338 , ValueShouldHaveTypeSignature (n "ExplicitTypeSignatures") "aNumber" (ShowFn (P.tyNumber ==))

339− , ValueShouldHaveTypeSignature (n "ExplicitTypeSignatures") "nestedForAll" (renderedType "forall c. (forall a b. c)")

340339 ])

341340

342341 , ("ConstrainedArgument",