Language.Futhark.TypeChecker.Unify

Documentation

data Constraint

Constructors

NoConstraint (Maybe Liftedness) SrcLoc

ParamType Liftedness SrcLoc

Constraint (TypeBase () ()) SrcLoc

Overloaded [PrimType] SrcLoc

HasFields (Map Name (TypeBase () ())) SrcLoc

Equality SrcLoc

HasConstrs [Name] SrcLoc

Instances

Show Constraint

Defined in Language.Futhark.TypeChecker.Unify

Methods

showsPrec :: Int -> Constraint -> ShowS

show :: Constraint -> String

showList :: [Constraint] -> ShowS

Located Constraint

Defined in Language.Futhark.TypeChecker.Unify

Methods

locOf :: Constraint -> Loc

locOfList :: [Constraint] -> Loc

type Constraints = Map VName Constraint

Mapping from fresh type variables, instantiated from the type schemes of polymorphic functions, to (possibly) specific types as determined on application and the location of that application, or a partial constraint on their type.

lookupSubst :: VName -> Constraints -> Maybe (Subst (TypeBase () ()))

class (MonadBreadCrumbs m, MonadError TypeError m) => MonadUnify m where

Minimal complete definition

getConstraints, putConstraints, newTypeVar

Methods

getConstraints :: m Constraints

putConstraints :: Constraints -> m ()

modifyConstraints :: (Constraints -> Constraints) -> m ()

newTypeVar :: Monoid als => SrcLoc -> String -> m (TypeBase dim als)

data BreadCrumb

A piece of information that describes what process the type checker currently performing. This is used to give better error messages.

Constructors

MatchingTypes (TypeBase () ()) (TypeBase () ())

MatchingFields Name

Instances

Show BreadCrumb

Defined in Language.Futhark.TypeChecker.Monad

Methods

showsPrec :: Int -> BreadCrumb -> ShowS

show :: BreadCrumb -> String

showList :: [BreadCrumb] -> ShowS

typeError :: (MonadError TypeError m, MonadBreadCrumbs m) => SrcLoc -> String -> m a

mkTypeVarName :: String -> Int -> Name

Construct a the name of a new type variable given a base description and a tag number (note that this is distinct from actually constructing a VName; the tag here is intended for human consumption but the machine does not care).

zeroOrderType :: (MonadUnify m, Pretty (ShapeDecl dim), Monoid as) => SrcLoc -> String -> TypeBase dim as -> m ()

mustHaveConstr :: MonadUnify m => SrcLoc -> Name -> TypeBase dim as -> m ()

mustHaveField :: (MonadUnify m, Monoid as) => SrcLoc -> Name -> TypeBase dim as -> m (TypeBase dim as)

mustBeOneOf :: MonadUnify m => [PrimType] -> SrcLoc -> TypeBase () () -> m ()

equalityType :: (MonadUnify m, Pretty (ShapeDecl dim), Monoid as) => SrcLoc -> TypeBase dim as -> m ()

normaliseType :: (Substitutable a, MonadUnify m) => a -> m a

unify :: MonadUnify m => SrcLoc -> TypeBase () () -> TypeBase () () -> m ()

Unifies two types.

doUnification :: SrcLoc -> [TypeParam] -> TypeBase () () -> TypeBase () () -> Either TypeError (TypeBase () ())

Perform a unification of two types outside a monadic context. The type parameters are allowed to be instantiated (with 'TypeParamDim ignored); all other types are considered rigid.