DsUtils

Utility functions for constructing Core syntax, principally for desugaring

Documentation

data EquationInfo

Constructors

EqnInfo

Fields

• eqn_pats :: [Pat GhcTc]

  The patterns for an equation

  NB: We have already applied decideBangHood to these patterns. See Note [decideBangHood] in DsUtils

• eqn_orig :: Origin

  Was this equation present in the user source?

  This helps us avoid warnings on patterns that GHC elaborated.

  For instance, the pattern -1 :: Word gets desugared into W# :: Word, but we shouldn't warn about an overflowed literal for both of these cases.

• eqn_rhs :: MatchResult

  What to do after match

Instances

Outputable EquationInfo

Defined in DsMonad

Methods

ppr :: EquationInfo -> SDoc

pprPrec :: Rational -> EquationInfo -> SDoc

firstPat :: EquationInfo -> Pat GhcTc

shiftEqns :: [EquationInfo] -> [EquationInfo]

data MatchResult

Constructors

MatchResult CanItFail (CoreExpr -> DsM CoreExpr)

data CanItFail

Constructors

CanFail

CantFail

data CaseAlt a

Constructors

MkCaseAlt

Fields

• alt_pat :: a
• alt_bndrs :: [Var]
• alt_wrapper :: HsWrapper
• alt_result :: MatchResult

cantFailMatchResult :: CoreExpr -> MatchResult

alwaysFailMatchResult :: MatchResult

extractMatchResult :: MatchResult -> CoreExpr -> DsM CoreExpr

combineMatchResults :: MatchResult -> MatchResult -> MatchResult

adjustMatchResult :: DsWrapper -> MatchResult -> MatchResult

adjustMatchResultDs :: (CoreExpr -> DsM CoreExpr) -> MatchResult -> MatchResult

mkCoLetMatchResult :: CoreBind -> MatchResult -> MatchResult

mkViewMatchResult :: Id -> CoreExpr -> MatchResult -> MatchResult

mkGuardedMatchResult :: CoreExpr -> MatchResult -> MatchResult

matchCanFail :: MatchResult -> Bool

mkEvalMatchResult :: Id -> Type -> MatchResult -> MatchResult

mkCoPrimCaseMatchResult :: Id -> Type -> [(Literal, MatchResult)] -> MatchResult

mkCoAlgCaseMatchResult :: Id -> Type -> [CaseAlt DataCon] -> MatchResult

mkCoSynCaseMatchResult :: Id -> Type -> CaseAlt PatSyn -> MatchResult

wrapBind :: Var -> Var -> CoreExpr -> CoreExpr

wrapBinds :: [(Var, Var)] -> CoreExpr -> CoreExpr

mkErrorAppDs :: Id -> Type -> SDoc -> DsM CoreExpr

mkCoreAppDs :: SDoc -> CoreExpr -> CoreExpr -> CoreExpr

mkCoreAppsDs :: SDoc -> CoreExpr -> [CoreExpr] -> CoreExpr

mkCastDs :: CoreExpr -> Coercion -> CoreExpr

seqVar :: Var -> CoreExpr -> CoreExpr

mkLHsPatTup :: [LPat GhcTc] -> LPat GhcTc

mkVanillaTuplePat :: [OutPat GhcTc] -> Boxity -> Pat GhcTc

mkBigLHsVarTupId :: [Id] -> LHsExpr GhcTc

mkBigLHsTupId :: [LHsExpr GhcTc] -> LHsExpr GhcTc

mkBigLHsVarPatTupId :: [Id] -> LPat GhcTc

mkBigLHsPatTupId :: [LPat GhcTc] -> LPat GhcTc

mkSelectorBinds

Arguments

:: [[Tickish Id]]

ticks to add, possibly

-> LPat GhcTc

The pattern

-> CoreExpr

Expression to which the pattern is bound

-> DsM (Id, [(Id, CoreExpr)])

Id the rhs is bound to, for desugaring strict binds (see Note [Desugar Strict binds] in DsBinds) and all the desugared binds

selectSimpleMatchVarL :: LPat GhcTc -> DsM Id

selectMatchVars :: [Pat GhcTc] -> DsM [Id]

selectMatchVar :: Pat GhcTc -> DsM Id

mkOptTickBox :: [Tickish Id] -> CoreExpr -> CoreExpr

mkBinaryTickBox :: Int -> Int -> CoreExpr -> DsM CoreExpr

decideBangHood

Arguments

:: DynFlags

-> LPat GhcTc

Original pattern

-> LPat GhcTc

Use -XStrict to add a ! or remove a ~ See Note [decideBangHood]

addBang

Arguments

:: LPat GhcTc

Original pattern

-> LPat GhcTc

Banged pattern

Unconditionally make a Pat strict.

isTrueLHsExpr :: LHsExpr GhcTc -> Maybe (CoreExpr -> DsM CoreExpr)