GHC.Rename.Utils

Documentation

checkDupRdrNames :: [LocatedN RdrName] -> RnM ()

checkDupRdrNamesN :: [LocatedN RdrName] -> RnM ()

checkShadowedRdrNames :: [LocatedN RdrName] -> RnM ()

checkDupNames :: [Name] -> RnM ()

checkDupAndShadowedNames :: (GlobalRdrEnv, LocalRdrEnv) -> [Name] -> RnM ()

dupNamesErr :: Outputable n => (n -> SrcSpan) -> NonEmpty n -> RnM ()

checkTupSize :: Int -> TcM ()

Ensure that a boxed or unboxed tuple has arity no larger than mAX_TUPLE_SIZE.

checkCTupSize :: Int -> TcM ()

Ensure that a constraint tuple has arity no larger than mAX_CTUPLE_SIZE.

addFvRn :: FreeVars -> RnM (thing, FreeVars) -> RnM (thing, FreeVars)

mapFvRn :: Traversable f => (a -> RnM (b, FreeVars)) -> f a -> RnM (f b, FreeVars)

mapMaybeFvRn :: (a -> RnM (b, FreeVars)) -> Maybe a -> RnM (Maybe b, FreeVars)

warnUnusedMatches :: [Name] -> FreeVars -> RnM ()

warnUnusedTypePatterns :: [Name] -> FreeVars -> RnM ()

warnUnusedTopBinds :: [GlobalRdrElt] -> RnM ()

warnUnusedLocalBinds :: [Name] -> FreeVars -> RnM ()

warnForallIdentifier :: LocatedN RdrName -> RnM ()

checkUnusedRecordWildcard :: SrcSpan -> FreeVars -> Maybe [Name] -> RnM ()

Checks to see if we need to warn for -Wunused-record-wildcards or -Wredundant-record-wildcards

mkFieldEnv :: GlobalRdrEnv -> NameEnv (FieldLabelString, Parent)

Make a map from selector names to field labels and parent tycon names, to be used when reporting unused record fields.

badQualBndrErr :: RdrName -> TcRnMessage

typeAppErr :: String -> LHsType GhcPs -> TcRnMessage

badFieldConErr :: Name -> FieldLabelString -> TcRnMessage

wrapGenSpan :: a -> LocatedAn an a

genHsVar :: Name -> HsExpr GhcRn

genLHsVar :: Name -> LHsExpr GhcRn

genHsApp :: HsExpr GhcRn -> LHsExpr GhcRn -> HsExpr GhcRn

genHsApps :: Name -> [LHsExpr GhcRn] -> HsExpr GhcRn

genAppType :: HsExpr GhcRn -> HsType (NoGhcTc GhcRn) -> HsExpr GhcRn

genHsIntegralLit :: IntegralLit -> LocatedAn an (HsExpr GhcRn)

genHsTyLit :: FastString -> HsType GhcRn

genSimpleConPat :: Name -> [LPat GhcRn] -> LPat GhcRn

genVarPat :: Name -> LPat GhcRn

genWildPat :: LPat GhcRn

genSimpleFunBind :: Name -> [LPat GhcRn] -> LHsExpr GhcRn -> LHsBind GhcRn

genFunBind :: LocatedN Name -> [LMatch GhcRn (LHsExpr GhcRn)] -> HsBind GhcRn

newLocalBndrRn :: LocatedN RdrName -> RnM Name

newLocalBndrsRn :: [LocatedN RdrName] -> RnM [Name]

bindLocalNames :: [Name] -> RnM a -> RnM a

bindLocalNamesFV :: [Name] -> RnM (a, FreeVars) -> RnM (a, FreeVars)

addNameClashErrRn :: RdrName -> NonEmpty GlobalRdrElt -> RnM ()

checkInferredVars

Arguments

:: HsDocContext

-> Maybe SDoc

The error msg if the signature is not allowed to contain manually written inferred variables.

-> LHsSigType GhcPs

-> RnM ()

Throw an error message if a user attempts to quantify an inferred type variable in a place where specificity cannot be observed. For example, forall {a}. [a] -> [a] would be rejected to the inferred type variable {a}, but forall a. [a] -> [a] would be accepted. See Note [Unobservably inferred type variables].

noNestedForallsContextsErr :: SDoc -> LHsType GhcRn -> Maybe (SrcSpan, TcRnMessage)

Examines a non-outermost type for foralls or contexts, which are assumed to be nested. For example, in the following declaration:

instance forall a. forall b. C (Either a b)

The outermost forall a is fine, but the nested forall b is not. We invoke noNestedForallsContextsErr on the type forall b. C (Either a b) to catch the nested forall and create a suitable error message. noNestedForallsContextsErr returns Just err_msg if such a forall or context is found, and returns Nothing otherwise.

This is currently used in the following places:

• In GADT constructor types (in rnConDecl). See Note [GADT abstract syntax] (Wrinkle: No nested foralls or contexts) in GHC.Hs.Type.
• In instance declaration types (in rnClsIntDecl and rnSrcDerivDecl in GHC.Rename.Module and renameSig in GHC.Rename.Bind). See Note [No nested foralls or contexts in instance types] in GHC.Hs.Type.

addNoNestedForallsContextsErr :: HsDocContext -> SDoc -> LHsType GhcRn -> RnM ()

A common way to invoke noNestedForallsContextsErr.