%
\section[HsBinds]{Abstract syntax: top-level bindings and signatures}
-Datatype for: @HsBinds@, @Bind@, @Sig@, @MonoBinds@.
+Datatype for: @BindGroup@, @Bind@, @Sig@, @Bind@.
\begin{code}
module HsBinds where
#include "HsVersions.h"
-import {-# SOURCE #-} HsExpr ( HsExpr, pprExpr,
- Match, pprFunBind,
- GRHSs, pprPatBind )
+import {-# SOURCE #-} HsExpr ( HsExpr, pprExpr, LHsExpr,
+ LMatch, pprFunBind,
+ GRHSs, pprPatBind )
-- friends:
-import HsImpExp ( pprHsVar )
-import HsPat ( Pat )
-import HsTypes ( HsType )
-import CoreSyn ( CoreExpr )
-import PprCore ( {- instance Outputable (Expr a) -} )
+import HsPat ( LPat )
+import HsTypes ( LHsType )
--others:
import Name ( Name )
-import PrelNames ( isUnboundName )
import NameSet ( NameSet, elemNameSet, nameSetToList )
-import BasicTypes ( RecFlag(..), FixitySig(..), Activation(..) )
+import BasicTypes ( IPName, RecFlag(..), Activation(..), Fixity )
import Outputable
-import SrcLoc ( SrcLoc )
+import SrcLoc ( Located(..), unLoc )
import Var ( TyVar )
-import Class ( DefMeth (..) )
+import Bag ( Bag, bagToList )
\end{code}
%************************************************************************
%* *
-\subsection{Bindings: @HsBinds@}
+\subsection{Bindings: @BindGroup@}
%* *
%************************************************************************
-The following syntax may produce new syntax which is not part of the input,
-and which is instead a translation of the input to the typechecker.
-Syntax translations are marked TRANSLATION in comments. New empty
-productions are useful in development but may not appear in the final
-grammar.
-
-Collections of bindings, created by dependency analysis and translation:
-
-\begin{code}
-data HsBinds id -- binders and bindees
- = EmptyBinds
-
- | ThenBinds (HsBinds id)
- (HsBinds id)
-
- | MonoBind (MonoBinds id)
- [Sig id] -- Empty on typechecker output, Type Signatures
- RecFlag
-\end{code}
+Global bindings (where clauses)
\begin{code}
-nullBinds :: HsBinds id -> Bool
+data HsBindGroup id
+ = HsBindGroup -- A mutually recursive group
+ (LHsBinds id)
+ [LSig id] -- Empty on typechecker output, Type Signatures
+ RecFlag
-nullBinds EmptyBinds = True
-nullBinds (ThenBinds b1 b2) = nullBinds b1 && nullBinds b2
-nullBinds (MonoBind b _ _) = nullMonoBinds b
+ | HsIPBinds
+ [LIPBind id] -- Not allowed at top level
-mkMonoBind :: MonoBinds id -> [Sig id] -> RecFlag -> HsBinds id
-mkMonoBind EmptyMonoBinds _ _ = EmptyBinds
-mkMonoBind mbinds sigs is_rec = MonoBind mbinds sigs is_rec
-\end{code}
-
-\begin{code}
-instance (OutputableBndr id) => Outputable (HsBinds id) where
- ppr binds = ppr_binds binds
-
-ppr_binds EmptyBinds = empty
-ppr_binds (ThenBinds binds1 binds2)
- = ppr_binds binds1 $$ ppr_binds binds2
-ppr_binds (MonoBind bind sigs is_rec)
+instance OutputableBndr id => Outputable (HsBindGroup id) where
+ ppr (HsBindGroup binds sigs is_rec)
= vcat [ppr_isrec,
vcat (map ppr sigs),
- ppr bind
+ vcat (map ppr (bagToList binds))
]
where
ppr_isrec = getPprStyle $ \ sty ->
case is_rec of
Recursive -> ptext SLIT("{- rec -}")
NonRecursive -> ptext SLIT("{- nonrec -}")
-\end{code}
-%************************************************************************
-%* *
-\subsection{Bindings: @MonoBinds@}
-%* *
-%************************************************************************
+ ppr (HsIPBinds ipbinds)
+ = vcat (map ppr ipbinds)
-Global bindings (where clauses)
+-- -----------------------------------------------------------------------------
+-- Implicit parameter bindings
-\begin{code}
-data MonoBinds id
- = EmptyMonoBinds
-
- | AndMonoBinds (MonoBinds id)
- (MonoBinds id)
-
- | FunMonoBind id -- Used for both functions f x = e
- -- and variables f = \x -> e
- -- Reason: the Match stuff lets us have an optional
- -- result type sig f :: a->a = ...mentions a...
- --
- -- This also means that instance decls can only have
- -- FunMonoBinds, so if you change this, you'll need to
- -- change e.g. rnMethodBinds
- Bool -- True => infix declaration
- [Match id]
- SrcLoc
-
- | PatMonoBind (Pat id) -- The pattern is never a simple variable;
- -- That case is done by FunMonoBind
- (GRHSs id)
- SrcLoc
-
- | VarMonoBind id -- TRANSLATION
- (HsExpr id)
-
- | CoreMonoBind id -- TRANSLATION
- CoreExpr -- No zonking; this is a final CoreExpr with Ids and Types!
+type LIPBind id = Located (IPBind id)
+
+-- | Implicit parameter bindings.
+data IPBind id
+ = IPBind
+ (IPName id)
+ (LHsExpr id)
+
+instance (OutputableBndr id) => Outputable (IPBind id) where
+ ppr (IPBind id rhs) = pprBndr LetBind id <+> equals <+> pprExpr (unLoc rhs)
+
+-- -----------------------------------------------------------------------------
+
+type LHsBinds id = Bag (LHsBind id)
+type LHsBind id = Located (HsBind id)
+
+data HsBind id
+ = FunBind (Located id)
+ -- Used for both functions f x = e
+ -- and variables f = \x -> e
+ -- Reason: the Match stuff lets us have an optional
+ -- result type sig f :: a->a = ...mentions a...
+ --
+ -- This also means that instance decls can only have
+ -- FunBinds, so if you change this, you'll need to
+ -- change e.g. rnMethodBinds
+ Bool -- True => infix declaration
+ [LMatch id]
+
+ | PatBind (LPat id) -- The pattern is never a simple variable;
+ -- That case is done by FunBind
+ (GRHSs id)
+
+ | VarBind id (Located (HsExpr id)) -- Dictionary binding and suchlike;
+ -- located only for consistency
| AbsBinds -- Binds abstraction; TRANSLATION
[TyVar] -- Type variables
[id] -- Dicts
[([TyVar], id, id)] -- (type variables, polymorphic, momonmorphic) triples
NameSet -- Set of *polymorphic* variables that have an INLINE pragma
- (MonoBinds id) -- The "business end"
+ (LHsBinds id) -- The "business end"
-- Creates bindings for *new* (polymorphic, overloaded) locals
-- in terms of *old* (monomorphic, non-overloaded) ones.
in (fm,gm)
\begin{code}
--- We keep the invariant that a MonoBinds is only empty
--- if it is exactly EmptyMonoBinds
-
-nullMonoBinds :: MonoBinds id -> Bool
-nullMonoBinds EmptyMonoBinds = True
-nullMonoBinds other_monobind = False
-
-andMonoBinds :: MonoBinds id -> MonoBinds id -> MonoBinds id
-andMonoBinds EmptyMonoBinds mb = mb
-andMonoBinds mb EmptyMonoBinds = mb
-andMonoBinds mb1 mb2 = AndMonoBinds mb1 mb2
-
-andMonoBindList :: [MonoBinds id] -> MonoBinds id
-andMonoBindList binds
- = loop1 binds
- where
- loop1 [] = EmptyMonoBinds
- loop1 (EmptyMonoBinds : binds) = loop1 binds
- loop1 (b:bs) = loop2 b bs
-
- -- acc is non-empty
- loop2 acc [] = acc
- loop2 acc (EmptyMonoBinds : bs) = loop2 acc bs
- loop2 acc (b:bs) = loop2 (acc `AndMonoBinds` b) bs
-\end{code}
-
-
-\begin{code}
-instance OutputableBndr id => Outputable (MonoBinds id) where
+instance OutputableBndr id => Outputable (HsBind id) where
ppr mbind = ppr_monobind mbind
+ppr_monobind :: OutputableBndr id => HsBind id -> SDoc
-ppr_monobind :: OutputableBndr id => MonoBinds id -> SDoc
-ppr_monobind EmptyMonoBinds = empty
-ppr_monobind (AndMonoBinds binds1 binds2)
- = ppr_monobind binds1 $$ ppr_monobind binds2
-
-ppr_monobind (PatMonoBind pat grhss locn) = pprPatBind pat grhss
-ppr_monobind (FunMonoBind fun inf matches locn) = pprFunBind fun matches
+ppr_monobind (PatBind pat grhss) = pprPatBind pat grhss
+ppr_monobind (VarBind var rhs) = ppr var <+> equals <+> pprExpr (unLoc rhs)
+ppr_monobind (FunBind fun inf matches) = pprFunBind (unLoc fun) matches
-- ToDo: print infix if appropriate
-ppr_monobind (VarMonoBind name expr)
- = sep [pprBndr LetBind name <+> equals, nest 4 (pprExpr expr)]
-
-ppr_monobind (CoreMonoBind name expr)
- = sep [pprBndr LetBind name <+> equals, nest 4 (ppr expr)]
-
ppr_monobind (AbsBinds tyvars dictvars exports inlines val_binds)
= sep [ptext SLIT("AbsBinds"),
brackets (interpp'SP tyvars),
serves for both.
\begin{code}
-data Sig name
- = Sig name -- a bog-std type signature
- (HsType name)
- SrcLoc
+type LSig name = Located (Sig name)
- | ClassOpSig name -- Selector name
- (DefMeth name) -- Default-method info
- -- See "THE NAMING STORY" in HsDecls
- (HsType name)
- SrcLoc
+data Sig name
+ = Sig (Located name) -- a bog-std type signature
+ (LHsType name)
- | SpecSig name -- specialise a function or datatype ...
- (HsType name) -- ... to these types
- SrcLoc
+ | SpecSig (Located name) -- specialise a function or datatype ...
+ (LHsType name) -- ... to these types
| InlineSig Bool -- True <=> INLINE f, False <=> NOINLINE f
- name -- Function name
+ (Located name) -- Function name
Activation -- When inlining is *active*
- SrcLoc
- | SpecInstSig (HsType name) -- (Class tys); should be a specialisation of the
+ | SpecInstSig (LHsType name) -- (Class tys); should be a specialisation of the
-- current instance decl
- SrcLoc
| FixSig (FixitySig name) -- Fixity declaration
+
+type LFixitySig name = Located (FixitySig name)
+data FixitySig name = FixitySig (Located name) Fixity
\end{code}
\begin{code}
-okBindSig :: NameSet -> Sig Name -> Bool
-okBindSig ns (ClassOpSig _ _ _ _) = False
-okBindSig ns sig = sigForThisGroup ns sig
+okBindSig :: NameSet -> LSig Name -> Bool
+okBindSig ns sig = sigForThisGroup ns sig
-okClsDclSig :: NameSet -> Sig Name -> Bool
-okClsDclSig ns (Sig _ _ _) = False
-okClsDclSig ns sig = sigForThisGroup ns sig
+okClsDclSig :: LSig Name -> Bool
+okClsDclSig (L _ (SpecInstSig _)) = False
+okClsDclSig sig = True -- All others OK
-okInstDclSig :: NameSet -> Sig Name -> Bool
-okInstDclSig ns (Sig _ _ _) = False
-okInstDclSig ns (FixSig _) = False
-okInstDclSig ns (SpecInstSig _ _) = True
-okInstDclSig ns sig = sigForThisGroup ns sig
+okInstDclSig :: NameSet -> LSig Name -> Bool
+okInstDclSig ns lsig@(L _ sig) = ok ns sig
+ where
+ ok ns (Sig _ _) = False
+ ok ns (FixSig _) = False
+ ok ns (SpecInstSig _) = True
+ ok ns sig = sigForThisGroup ns lsig
-sigForThisGroup ns sig
+sigForThisGroup :: NameSet -> LSig Name -> Bool
+sigForThisGroup ns sig
= case sigName sig of
- Nothing -> False
- Just n | isUnboundName n -> True -- Don't complain about an unbound name again
- | otherwise -> n `elemNameSet` ns
-
-sigName :: Sig name -> Maybe name
-sigName (Sig n _ _) = Just n
-sigName (ClassOpSig n _ _ _) = Just n
-sigName (SpecSig n _ _) = Just n
-sigName (InlineSig _ n _ _) = Just n
-sigName (FixSig (FixitySig n _ _)) = Just n
-sigName other = Nothing
+ Nothing -> False
+ Just n -> n `elemNameSet` ns
+
+sigName :: LSig name -> Maybe name
+sigName (L _ sig) = f sig
+ where
+ f (Sig n _) = Just (unLoc n)
+ f (SpecSig n _) = Just (unLoc n)
+ f (InlineSig _ n _) = Just (unLoc n)
+ f (FixSig (FixitySig n _)) = Just (unLoc n)
+ f other = Nothing
isFixitySig :: Sig name -> Bool
isFixitySig (FixSig _) = True
isFixitySig _ = False
-isClassOpSig :: Sig name -> Bool
-isClassOpSig (ClassOpSig _ _ _ _) = True
-isClassOpSig _ = False
-
isPragSig :: Sig name -> Bool
-- Identifies pragmas
-isPragSig (SpecSig _ _ _) = True
-isPragSig (InlineSig _ _ _ _) = True
-isPragSig (SpecInstSig _ _) = True
-isPragSig other = False
+isPragSig (SpecSig _ _) = True
+isPragSig (InlineSig _ _ _) = True
+isPragSig (SpecInstSig _) = True
+isPragSig other = False
+
+hsSigDoc (Sig _ _) = ptext SLIT("type signature")
+hsSigDoc (SpecSig _ _) = ptext SLIT("SPECIALISE pragma")
+hsSigDoc (InlineSig True _ _) = ptext SLIT("INLINE pragma")
+hsSigDoc (InlineSig False _ _) = ptext SLIT("NOINLINE pragma")
+hsSigDoc (SpecInstSig _) = ptext SLIT("SPECIALISE instance pragma")
+hsSigDoc (FixSig (FixitySig _ _)) = ptext SLIT("fixity declaration")
\end{code}
+Signature equality is used when checking for duplicate signatures
+
\begin{code}
-hsSigDoc (Sig _ _ loc) = (ptext SLIT("type signature"),loc)
-hsSigDoc (ClassOpSig _ _ _ loc) = (ptext SLIT("class-method type signature"), loc)
-hsSigDoc (SpecSig _ _ loc) = (ptext SLIT("SPECIALISE pragma"),loc)
-hsSigDoc (InlineSig True _ _ loc) = (ptext SLIT("INLINE pragma"),loc)
-hsSigDoc (InlineSig False _ _ loc) = (ptext SLIT("NOINLINE pragma"),loc)
-hsSigDoc (SpecInstSig _ loc) = (ptext SLIT("SPECIALISE instance pragma"),loc)
-hsSigDoc (FixSig (FixitySig _ _ loc)) = (ptext SLIT("fixity declaration"), loc)
+eqHsSig :: Sig Name -> Sig Name -> Bool
+eqHsSig (FixSig (FixitySig n1 _)) (FixSig (FixitySig n2 _)) = unLoc n1 == unLoc n2
+eqHsSig (Sig n1 _) (Sig n2 _) = unLoc n1 == unLoc n2
+eqHsSig (InlineSig b1 n1 _) (InlineSig b2 n2 _) = b1 == b2 && unLoc n1 == unLoc n2
+ -- For specialisations, we don't have equality over
+ -- HsType, so it's not convenient to spot duplicate
+ -- specialisations here. Check for this later, when we're in Type land
+eqHsSig _other1 _other2 = False
\end{code}
\begin{code}
-instance (Outputable name) => Outputable (Sig name) where
+instance (OutputableBndr name) => Outputable (Sig name) where
ppr sig = ppr_sig sig
-ppr_sig :: Outputable name => Sig name -> SDoc
-ppr_sig (Sig var ty _)
+ppr_sig :: OutputableBndr name => Sig name -> SDoc
+ppr_sig (Sig var ty)
= sep [ppr var <+> dcolon, nest 4 (ppr ty)]
-ppr_sig (ClassOpSig var dm ty _)
- = sep [ pprHsVar var <+> dcolon,
- nest 4 (ppr ty),
- nest 4 (pp_dm_comment) ]
- where
- pp_dm = case dm of
- DefMeth _ -> equals -- Default method indicator
- GenDefMeth -> semi -- Generic method indicator
- NoDefMeth -> empty -- No Method at all
- pp_dm_comment = case dm of
- DefMeth _ -> text "{- has default method -}"
- GenDefMeth -> text "{- has generic method -}"
- NoDefMeth -> empty -- No Method at all
-
-ppr_sig (SpecSig var ty _)
+ppr_sig (SpecSig var ty)
= sep [ hsep [text "{-# SPECIALIZE", ppr var, dcolon],
nest 4 (ppr ty <+> text "#-}")
]
-ppr_sig (InlineSig True var phase _)
+ppr_sig (InlineSig True var phase)
= hsep [text "{-# INLINE", ppr phase, ppr var, text "#-}"]
-ppr_sig (InlineSig False var phase _)
+ppr_sig (InlineSig False var phase)
= hsep [text "{-# NOINLINE", ppr phase, ppr var, text "#-}"]
-ppr_sig (SpecInstSig ty _)
+ppr_sig (SpecInstSig ty)
= hsep [text "{-# SPECIALIZE instance", ppr ty, text "#-}"]
ppr_sig (FixSig fix_sig) = ppr fix_sig
-\end{code}
-
-Checking for distinct signatures; oh, so boring
-
-\begin{code}
-eqHsSig :: Sig Name -> Sig Name -> Bool
-eqHsSig (Sig n1 _ _) (Sig n2 _ _) = n1 == n2
-eqHsSig (InlineSig b1 n1 _ _)(InlineSig b2 n2 _ _) = b1 == b2 && n1 == n2
-
-eqHsSig (SpecInstSig ty1 _) (SpecInstSig ty2 _) = ty1 == ty2
-eqHsSig (SpecSig n1 ty1 _) (SpecSig n2 ty2 _) =
- -- may have many specialisations for one value;
- -- but not ones that are exactly the same...
- (n1 == n2) && (ty1 == ty2)
-
-eqHsSig _other1 _other2 = False
+instance Outputable name => Outputable (FixitySig name) where
+ ppr (FixitySig name fixity) = sep [ppr fixity, ppr name]
\end{code}
projects / ghc-hetmet.git / blobdiff