TcSimplify

Documentation

simplifyInfer :: TcLevel -> InferMode -> [TcIdSigInst] -> [(Name, TcTauType)] -> WantedConstraints -> TcM ([TcTyVar], [EvVar], TcEvBinds, WantedConstraints, Bool)

data InferMode

How should we choose which constraints to quantify over?

Constructors

ApplyMR

Apply the monomorphism restriction, never quantifying over any constraints

EagerDefaulting

See Note [TcRnExprMode] in TcRnDriver, the :type +d case; this mode refuses to quantify over any defaultable constraint

NoRestrictions

Quantify over any constraint that satisfies TcType.pickQuantifiablePreds

Instances

Outputable InferMode

Defined in TcSimplify

Methods

ppr :: InferMode -> SDoc

pprPrec :: Rational -> InferMode -> SDoc

growThetaTyVars :: ThetaType -> TyCoVarSet -> TyCoVarSet

simplifyAmbiguityCheck :: Type -> WantedConstraints -> TcM ()

simplifyDefault :: ThetaType -> TcM ()

simplifyTop :: WantedConstraints -> TcM (Bag EvBind)

simplifyTopImplic :: Bag Implication -> TcM ()

simplifyInteractive :: WantedConstraints -> TcM (Bag EvBind)

solveEqualities :: TcM a -> TcM a

Type-check a thing that emits only equality constraints, then solve those constraints. Fails outright if there is trouble. Use this if you're not going to get another crack at solving (because, e.g., you're checking a datatype declaration)

solveLocalEqualities :: String -> TcM a -> TcM a

Type-check a thing that emits only equality constraints, solving any constraints we can and re-emitting constraints that we can't. The thing_inside should generally bump the TcLevel to make sure that this run of the solver doesn't affect anything lying around.

solveLocalEqualitiesX :: String -> TcM a -> TcM (WantedConstraints, a)

simplifyWantedsTcM :: [CtEvidence] -> TcM WantedConstraints

tcCheckSatisfiability :: Bag EvVar -> TcM Bool

tcNormalise :: Bag EvVar -> Type -> TcM Type

Normalise a type as much as possible using the given constraints. See Note [tcNormalise].

captureTopConstraints :: TcM a -> TcM (a, WantedConstraints)

simpl_top :: WantedConstraints -> TcS WantedConstraints

Simplify top-level constraints, but without reporting any unsolved constraints nor unsafe overlapping.

promoteTyVar :: TcTyVar -> TcM (Bool, TcTyVar)

promoteTyVarSet :: TcTyVarSet -> TcM (Bool, TcTyVarSet)

solveWanteds :: WantedConstraints -> TcS WantedConstraints

solveWantedsAndDrop :: WantedConstraints -> TcS WantedConstraints

approximateWC :: Bool -> WantedConstraints -> Cts

runTcSDeriveds :: TcS a -> TcM a

This variant of runTcS will keep solving, even when only Deriveds are left around. It also doesn't return any evidence, as callers won't need it.