%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[HsDecls]{Abstract syntax: global declarations}
-Definitions for: @FixityDecl@, @TyDecl@ and @ConDecl@, @ClassDecl@,
+Definitions for: @TyDecl@ and @oCnDecl@, @ClassDecl@,
@InstDecl@, @DefaultDecl@ and @ForeignDecl@.
\begin{code}
-module HsDecls where
+module HsDecls (
+ HsDecl(..), LHsDecl, TyClDecl(..), LTyClDecl,
+ InstDecl(..), LInstDecl, NewOrData(..),
+ RuleDecl(..), LRuleDecl, RuleBndr(..),
+ DefaultDecl(..), LDefaultDecl, SpliceDecl(..),
+ ForeignDecl(..), LForeignDecl, ForeignImport(..), ForeignExport(..),
+ CImportSpec(..), FoType(..),
+ ConDecl(..), ResType(..), LConDecl,
+ DeprecDecl(..), LDeprecDecl,
+ HsGroup(..), emptyRdrGroup, emptyRnGroup, appendGroups,
+ tcdName, tyClDeclNames, tyClDeclTyVars,
+ isClassDecl, isSynDecl, isDataDecl,
+ countTyClDecls,
+ conDetailsTys,
+ collectRuleBndrSigTys,
+ ) where
#include "HsVersions.h"
-- friends:
-import HsBinds ( HsBinds, MonoBinds, Sig, nullMonoBinds )
-import HsPragmas ( DataPragmas, ClassPragmas )
+import {-# SOURCE #-} HsExpr( HsExpr, pprExpr )
+ -- Because Expr imports Decls via HsBracket
+
+import HsBinds ( HsValBinds(..), HsBind, LHsBinds, plusHsValBinds,
+ Sig(..), LSig, LFixitySig, pprLHsBinds,
+ emptyValBindsIn, emptyValBindsOut )
+import HsPat ( HsConDetails(..), hsConArgs )
+import HsImpExp ( pprHsVar )
import HsTypes
-import HsCore ( UfExpr )
-import BasicTypes ( Fixity, NewOrData(..) )
-import IdInfo ( ArgUsageInfo, FBTypeInfo, ArityInfo, UpdateInfo )
-import Demand ( Demand )
-import CallConv ( CallConv, pprCallConv )
+import HscTypes ( DeprecTxt )
+import CoreSyn ( RuleName )
+import Kind ( Kind, pprKind )
+import BasicTypes ( Activation(..) )
+import ForeignCall ( CCallTarget(..), DNCallSpec, CCallConv, Safety,
+ CExportSpec(..), CLabelString )
-- others:
-import Name ( getOccName, OccName, NamedThing(..) )
+import FunDeps ( pprFundeps )
+import Class ( FunDep )
import Outputable
-import SrcLoc ( SrcLoc )
-import Util
+import Util ( count )
+import SrcLoc ( Located(..), unLoc, noLoc )
+import FastString
\end{code}
%************************************************************************
\begin{code}
-data HsDecl flexi name pat
- = TyD (TyDecl name)
- | ClD (ClassDecl flexi name pat)
- | InstD (InstDecl flexi name pat)
- | DefD (DefaultDecl name)
- | ValD (HsBinds flexi name pat)
- | SigD (IfaceSig name)
- | ForD (ForeignDecl name)
+type LHsDecl id = Located (HsDecl id)
+
+data HsDecl id
+ = TyClD (TyClDecl id)
+ | InstD (InstDecl id)
+ | ValD (HsBind id)
+ | SigD (Sig id)
+ | DefD (DefaultDecl id)
+ | ForD (ForeignDecl id)
+ | DeprecD (DeprecDecl id)
+ | RuleD (RuleDecl id)
+ | SpliceD (SpliceDecl id)
+
+-- NB: all top-level fixity decls are contained EITHER
+-- EITHER SigDs
+-- OR in the ClassDecls in TyClDs
+--
+-- The former covers
+-- a) data constructors
+-- b) class methods (but they can be also done in the
+-- signatures of class decls)
+-- c) imported functions (that have an IfacSig)
+-- d) top level decls
+--
+-- The latter is for class methods only
+
+-- A [HsDecl] is categorised into a HsGroup before being
+-- fed to the renamer.
+data HsGroup id
+ = HsGroup {
+ hs_valds :: HsValBinds id,
+ hs_tyclds :: [LTyClDecl id],
+ hs_instds :: [LInstDecl id],
+
+ hs_fixds :: [LFixitySig id],
+ -- Snaffled out of both top-level fixity signatures,
+ -- and those in class declarations
+
+ hs_defds :: [LDefaultDecl id],
+ hs_fords :: [LForeignDecl id],
+ hs_depds :: [LDeprecDecl id],
+ hs_ruleds :: [LRuleDecl id]
+ }
+
+emptyGroup, emptyRdrGroup, emptyRnGroup :: HsGroup a
+emptyRdrGroup = emptyGroup { hs_valds = emptyValBindsIn }
+emptyRnGroup = emptyGroup { hs_valds = emptyValBindsOut }
+
+emptyGroup = HsGroup { hs_tyclds = [], hs_instds = [],
+ hs_fixds = [], hs_defds = [], hs_fords = [],
+ hs_depds = [], hs_ruleds = [],
+ hs_valds = error "emptyGroup hs_valds: Can't happen" }
+
+appendGroups :: HsGroup a -> HsGroup a -> HsGroup a
+appendGroups
+ HsGroup {
+ hs_valds = val_groups1,
+ hs_tyclds = tyclds1,
+ hs_instds = instds1,
+ hs_fixds = fixds1,
+ hs_defds = defds1,
+ hs_fords = fords1,
+ hs_depds = depds1,
+ hs_ruleds = rulds1 }
+ HsGroup {
+ hs_valds = val_groups2,
+ hs_tyclds = tyclds2,
+ hs_instds = instds2,
+ hs_fixds = fixds2,
+ hs_defds = defds2,
+ hs_fords = fords2,
+ hs_depds = depds2,
+ hs_ruleds = rulds2 }
+ =
+ HsGroup {
+ hs_valds = val_groups1 `plusHsValBinds` val_groups2,
+ hs_tyclds = tyclds1 ++ tyclds2,
+ hs_instds = instds1 ++ instds2,
+ hs_fixds = fixds1 ++ fixds2,
+ hs_defds = defds1 ++ defds2,
+ hs_fords = fords1 ++ fords2,
+ hs_depds = depds1 ++ depds2,
+ hs_ruleds = rulds1 ++ rulds2 }
\end{code}
\begin{code}
-#ifdef DEBUG
-hsDeclName :: (NamedThing name, Outputable name, Outputable pat)
- => HsDecl flexi name pat -> name
-#endif
-hsDeclName (TyD (TyData _ _ name _ _ _ _ _)) = name
-hsDeclName (TyD (TySynonym name _ _ _)) = name
-hsDeclName (ClD (ClassDecl _ name _ _ _ _ _ _ _)) = name
-hsDeclName (SigD (IfaceSig name _ _ _)) = name
-hsDeclName (InstD (InstDecl _ _ _ (Just name) _)) = name
-hsDeclName (ForD (ForeignDecl name _ _ _ _ _)) = name
--- Others don't make sense
-#ifdef DEBUG
-hsDeclName x = pprPanic "HsDecls.hsDeclName" (ppr x)
-#endif
-\end{code}
-
-\begin{code}
-instance (NamedThing name, Outputable name, Outputable pat)
- => Outputable (HsDecl flexi name pat) where
-
- ppr (TyD td) = ppr td
- ppr (ClD cd) = ppr cd
- ppr (SigD sig) = ppr sig
+instance OutputableBndr name => Outputable (HsDecl name) where
+ ppr (TyClD dcl) = ppr dcl
ppr (ValD binds) = ppr binds
ppr (DefD def) = ppr def
ppr (InstD inst) = ppr inst
ppr (ForD fd) = ppr fd
-
-#ifdef DEBUG
--- hsDeclName needs more context when DEBUG is on
-instance (NamedThing name, Outputable name, Outputable pat, Eq name)
- => Eq (HsDecl flex name pat) where
- d1 == d2 = hsDeclName d1 == hsDeclName d2
-
-instance (NamedThing name, Outputable name, Outputable pat, Ord name)
- => Ord (HsDecl flex name pat) where
- d1 `compare` d2 = hsDeclName d1 `compare` hsDeclName d2
-#else
-instance (Eq name) => Eq (HsDecl flex name pat) where
- d1 == d2 = hsDeclName d1 == hsDeclName d2
-
-instance (Ord name) => Ord (HsDecl flexi name pat) where
- d1 `compare` d2 = hsDeclName d1 `compare` hsDeclName d2
-#endif
+ ppr (SigD sd) = ppr sd
+ ppr (RuleD rd) = ppr rd
+ ppr (DeprecD dd) = ppr dd
+ ppr (SpliceD dd) = ppr dd
+
+instance OutputableBndr name => Outputable (HsGroup name) where
+ ppr (HsGroup { hs_valds = val_decls,
+ hs_tyclds = tycl_decls,
+ hs_instds = inst_decls,
+ hs_fixds = fix_decls,
+ hs_depds = deprec_decls,
+ hs_fords = foreign_decls,
+ hs_defds = default_decls,
+ hs_ruleds = rule_decls })
+ = vcat [ppr_ds fix_decls, ppr_ds default_decls,
+ ppr_ds deprec_decls, ppr_ds rule_decls,
+ ppr val_decls,
+ ppr_ds tycl_decls, ppr_ds inst_decls,
+ ppr_ds foreign_decls]
+ where
+ ppr_ds [] = empty
+ ppr_ds ds = text "" $$ vcat (map ppr ds)
+
+data SpliceDecl id = SpliceDecl (Located (HsExpr id)) -- Top level splice
+
+instance OutputableBndr name => Outputable (SpliceDecl name) where
+ ppr (SpliceDecl e) = ptext SLIT("$") <> parens (pprExpr (unLoc e))
\end{code}
%************************************************************************
%* *
-\subsection[FixityDecl]{A fixity declaration}
+\subsection[TyDecl]{@data@, @newtype@ or @type@ (synonym) type declaration}
%* *
%************************************************************************
-\begin{code}
-data FixityDecl name = FixityDecl name Fixity SrcLoc
+ --------------------------------
+ THE NAMING STORY
+ --------------------------------
+
+Here is the story about the implicit names that go with type, class,
+and instance decls. It's a bit tricky, so pay attention!
+
+"Implicit" (or "system") binders
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ Each data type decl defines
+ a worker name for each constructor
+ to-T and from-T convertors
+ Each class decl defines
+ a tycon for the class
+ a data constructor for that tycon
+ the worker for that constructor
+ a selector for each superclass
+
+All have occurrence names that are derived uniquely from their parent
+declaration.
+
+None of these get separate definitions in an interface file; they are
+fully defined by the data or class decl. But they may *occur* in
+interface files, of course. Any such occurrence must haul in the
+relevant type or class decl.
+
+Plan of attack:
+ - Ensure they "point to" the parent data/class decl
+ when loading that decl from an interface file
+ (See RnHiFiles.getSysBinders)
+
+ - When typechecking the decl, we build the implicit TyCons and Ids.
+ When doing so we look them up in the name cache (RnEnv.lookupSysName),
+ to ensure correct module and provenance is set
+
+These are the two places that we have to conjure up the magic derived
+names. (The actual magic is in OccName.mkWorkerOcc, etc.)
+
+Default methods
+~~~~~~~~~~~~~~~
+ - Occurrence name is derived uniquely from the method name
+ E.g. $dmmax
+
+ - If there is a default method name at all, it's recorded in
+ the ClassOpSig (in HsBinds), in the DefMeth field.
+ (DefMeth is defined in Class.lhs)
+
+Source-code class decls and interface-code class decls are treated subtly
+differently, which has given me a great deal of confusion over the years.
+Here's the deal. (We distinguish the two cases because source-code decls
+have (Just binds) in the tcdMeths field, whereas interface decls have Nothing.
+
+In *source-code* class declarations:
+
+ - When parsing, every ClassOpSig gets a DefMeth with a suitable RdrName
+ This is done by RdrHsSyn.mkClassOpSigDM
+
+ - The renamer renames it to a Name
+
+ - During typechecking, we generate a binding for each $dm for
+ which there's a programmer-supplied default method:
+ class Foo a where
+ op1 :: <type>
+ op2 :: <type>
+ op1 = ...
+ We generate a binding for $dmop1 but not for $dmop2.
+ The Class for Foo has a NoDefMeth for op2 and a DefMeth for op1.
+ The Name for $dmop2 is simply discarded.
+
+In *interface-file* class declarations:
+ - When parsing, we see if there's an explicit programmer-supplied default method
+ because there's an '=' sign to indicate it:
+ class Foo a where
+ op1 = :: <type> -- NB the '='
+ op2 :: <type>
+ We use this info to generate a DefMeth with a suitable RdrName for op1,
+ and a NoDefMeth for op2
+ - The interface file has a separate definition for $dmop1, with unfolding etc.
+ - The renamer renames it to a Name.
+ - The renamer treats $dmop1 as a free variable of the declaration, so that
+ the binding for $dmop1 will be sucked in. (See RnHsSyn.tyClDeclFVs)
+ This doesn't happen for source code class decls, because they *bind* the default method.
+
+Dictionary functions
+~~~~~~~~~~~~~~~~~~~~
+Each instance declaration gives rise to one dictionary function binding.
+
+The type checker makes up new source-code instance declarations
+(e.g. from 'deriving' or generic default methods --- see
+TcInstDcls.tcInstDecls1). So we can't generate the names for
+dictionary functions in advance (we don't know how many we need).
+
+On the other hand for interface-file instance declarations, the decl
+specifies the name of the dictionary function, and it has a binding elsewhere
+in the interface file:
+ instance {Eq Int} = dEqInt
+ dEqInt :: {Eq Int} <pragma info>
+
+So again we treat source code and interface file code slightly differently.
+
+Source code:
+ - Source code instance decls have a Nothing in the (Maybe name) field
+ (see data InstDecl below)
+
+ - The typechecker makes up a Local name for the dict fun for any source-code
+ instance decl, whether it comes from a source-code instance decl, or whether
+ the instance decl is derived from some other construct (e.g. 'deriving').
+
+ - The occurrence name it chooses is derived from the instance decl (just for
+ documentation really) --- e.g. dNumInt. Two dict funs may share a common
+ occurrence name, but will have different uniques. E.g.
+ instance Foo [Int] where ...
+ instance Foo [Bool] where ...
+ These might both be dFooList
+
+ - The CoreTidy phase externalises the name, and ensures the occurrence name is
+ unique (this isn't special to dict funs). So we'd get dFooList and dFooList1.
+
+ - We can take this relaxed approach (changing the occurrence name later)
+ because dict fun Ids are not captured in a TyCon or Class (unlike default
+ methods, say). Instead, they are kept separately in the InstEnv. This
+ makes it easy to adjust them after compiling a module. (Once we've finished
+ compiling that module, they don't change any more.)
+
+
+Interface file code:
+ - The instance decl gives the dict fun name, so the InstDecl has a (Just name)
+ in the (Maybe name) field.
+
+ - RnHsSyn.instDeclFVs treats the dict fun name as free in the decl, so that we
+ suck in the dfun binding
+
-instance Outputable name => Outputable (FixityDecl name) where
- ppr (FixityDecl name fixity loc) = sep [ppr fixity, ppr name]
+\begin{code}
+-- TyClDecls are precisely the kind of declarations that can
+-- appear in interface files; or (internally) in GHC's interface
+-- for a module. That's why (despite the misnomer) IfaceSig and ForeignType
+-- are both in TyClDecl
+
+type LTyClDecl name = Located (TyClDecl name)
+
+data TyClDecl name
+ = ForeignType {
+ tcdLName :: Located name,
+ tcdExtName :: Maybe FastString,
+ tcdFoType :: FoType
+ }
+
+ | TyData { tcdND :: NewOrData,
+ tcdCtxt :: LHsContext name, -- Context
+ tcdLName :: Located name, -- Type constructor
+ tcdTyVars :: [LHsTyVarBndr name], -- Type variables
+ tcdKindSig :: Maybe Kind, -- Optional kind sig;
+ -- (only for the 'where' form)
+
+ tcdCons :: [LConDecl name], -- Data constructors
+ -- For data T a = T1 | T2 a the LConDecls all have ResTyH98
+ -- For data T a where { T1 :: T a } the LConDecls all have ResTyGADT
+
+ tcdDerivs :: Maybe [LHsType name]
+ -- Derivings; Nothing => not specified
+ -- Just [] => derive exactly what is asked
+ -- These "types" must be of form
+ -- forall ab. C ty1 ty2
+ -- Typically the foralls and ty args are empty, but they
+ -- are non-empty for the newtype-deriving case
+ }
+
+ | TySynonym { tcdLName :: Located name, -- type constructor
+ tcdTyVars :: [LHsTyVarBndr name], -- type variables
+ tcdSynRhs :: LHsType name -- synonym expansion
+ }
+
+ | ClassDecl { tcdCtxt :: LHsContext name, -- Context...
+ tcdLName :: Located name, -- Name of the class
+ tcdTyVars :: [LHsTyVarBndr name], -- Class type variables
+ tcdFDs :: [Located (FunDep name)], -- Functional deps
+ tcdSigs :: [LSig name], -- Methods' signatures
+ tcdMeths :: LHsBinds name -- Default methods
+ }
+
+data NewOrData
+ = NewType -- "newtype Blah ..."
+ | DataType -- "data Blah ..."
+ deriving( Eq ) -- Needed because Demand derives Eq
\end{code}
+Simple classifiers
-%************************************************************************
-%* *
-\subsection[TyDecl]{@data@, @newtype@ or @type@ (synonym) type declaration}
-%* *
-%************************************************************************
+\begin{code}
+isDataDecl, isSynDecl, isClassDecl :: TyClDecl name -> Bool
+
+isSynDecl (TySynonym {}) = True
+isSynDecl other = False
+
+isDataDecl (TyData {}) = True
+isDataDecl other = False
+
+isClassDecl (ClassDecl {}) = True
+isClassDecl other = False
+\end{code}
+
+Dealing with names
\begin{code}
-data TyDecl name
- = TyData NewOrData
- (Context name) -- context
- name -- type constructor
- [HsTyVar name] -- type variables
- [ConDecl name] -- data constructors (empty if abstract)
- (Maybe [name]) -- derivings; Nothing => not specified
- -- (i.e., derive default); Just [] => derive
- -- *nothing*; Just <list> => as you would
- -- expect...
- (DataPragmas name)
- SrcLoc
-
- | TySynonym name -- type constructor
- [HsTyVar name] -- type variables
- (HsType name) -- synonym expansion
- SrcLoc
+tcdName :: TyClDecl name -> name
+tcdName decl = unLoc (tcdLName decl)
+
+tyClDeclNames :: Eq name => TyClDecl name -> [Located name]
+-- Returns all the *binding* names of the decl, along with their SrcLocs
+-- The first one is guaranteed to be the name of the decl
+-- For record fields, the first one counts as the SrcLoc
+-- We use the equality to filter out duplicate field names
+tyClDeclNames (TySynonym {tcdLName = name}) = [name]
+tyClDeclNames (ForeignType {tcdLName = name}) = [name]
+
+tyClDeclNames (ClassDecl {tcdLName = cls_name, tcdSigs = sigs})
+ = cls_name : [n | L _ (TypeSig n _) <- sigs]
+
+tyClDeclNames (TyData {tcdLName = tc_name, tcdCons = cons})
+ = tc_name : conDeclsNames (map unLoc cons)
+
+tyClDeclTyVars (TySynonym {tcdTyVars = tvs}) = tvs
+tyClDeclTyVars (TyData {tcdTyVars = tvs}) = tvs
+tyClDeclTyVars (ClassDecl {tcdTyVars = tvs}) = tvs
+tyClDeclTyVars (ForeignType {}) = []
+\end{code}
+
+\begin{code}
+countTyClDecls :: [TyClDecl name] -> (Int, Int, Int, Int)
+ -- class, data, newtype, synonym decls
+countTyClDecls decls
+ = (count isClassDecl decls,
+ count isSynDecl decls,
+ count isDataTy decls,
+ count isNewTy decls)
+ where
+ isDataTy TyData{tcdND=DataType} = True
+ isDataTy _ = False
+
+ isNewTy TyData{tcdND=NewType} = True
+ isNewTy _ = False
\end{code}
\begin{code}
-instance (NamedThing name, Outputable name)
- => Outputable (TyDecl name) where
+instance OutputableBndr name
+ => Outputable (TyClDecl name) where
- ppr (TySynonym tycon tyvars mono_ty src_loc)
- = hang (pp_decl_head SLIT("type") empty tycon tyvars)
+ ppr (ForeignType {tcdLName = ltycon})
+ = hsep [ptext SLIT("foreign import type dotnet"), ppr ltycon]
+
+ ppr (TySynonym {tcdLName = ltycon, tcdTyVars = tyvars, tcdSynRhs = mono_ty})
+ = hang (ptext SLIT("type") <+> pp_decl_head [] ltycon tyvars <+> equals)
4 (ppr mono_ty)
- ppr (TyData new_or_data context tycon tyvars condecls derivings pragmas src_loc)
- = pp_tydecl
- (pp_decl_head keyword (pp_context_and_arrow context) tycon tyvars)
+ ppr (TyData {tcdND = new_or_data, tcdCtxt = context, tcdLName = ltycon,
+ tcdTyVars = tyvars, tcdKindSig = mb_sig, tcdCons = condecls,
+ tcdDerivs = derivings})
+ = pp_tydecl (ppr new_or_data <+> pp_decl_head (unLoc context) ltycon tyvars <+> ppr_sig mb_sig)
(pp_condecls condecls)
derivings
where
- keyword = case new_or_data of
- NewType -> SLIT("newtype")
- DataType -> SLIT("data")
+ ppr_sig Nothing = empty
+ ppr_sig (Just kind) = dcolon <+> pprKind kind
-pp_decl_head str pp_context tycon tyvars
- = hsep [ptext str, pp_context, ppr tycon,
- interppSP tyvars, ptext SLIT("=")]
+ ppr (ClassDecl {tcdCtxt = context, tcdLName = lclas, tcdTyVars = tyvars, tcdFDs = fds,
+ tcdSigs = sigs, tcdMeths = methods})
+ | null sigs -- No "where" part
+ = top_matter
-pp_condecls [] = empty -- Curious!
-pp_condecls (c:cs)
- = sep (ppr c : map (\ c -> (<>) (ptext SLIT("| ")) (ppr c)) cs)
+ | otherwise -- Laid out
+ = sep [hsep [top_matter, ptext SLIT("where {")],
+ nest 4 (sep [sep (map ppr_sig sigs), ppr methods, char '}'])]
+ where
+ top_matter = ptext SLIT("class") <+> pp_decl_head (unLoc context) lclas tyvars <+> pprFundeps (map unLoc fds)
+ ppr_sig sig = ppr sig <> semi
+
+pp_decl_head :: OutputableBndr name
+ => HsContext name
+ -> Located name
+ -> [LHsTyVarBndr name]
+ -> SDoc
+pp_decl_head context thing tyvars
+ = hsep [pprHsContext context, ppr thing, interppSP tyvars]
+pp_condecls cs@(L _ ConDecl{ con_res = ResTyGADT _ } : _) -- In GADT syntax
+ = hang (ptext SLIT("where")) 2 (vcat (map ppr cs))
+pp_condecls cs -- In H98 syntax
+ = equals <+> sep (punctuate (ptext SLIT(" |")) (map ppr cs))
pp_tydecl pp_head pp_decl_rhs derivings
= hang pp_head 4 (sep [
Just ds -> hsep [ptext SLIT("deriving"), parens (interpp'SP ds)]
])
-pp_context_and_arrow :: Outputable name => Context name -> SDoc
-pp_context_and_arrow [] = empty
-pp_context_and_arrow theta = hsep [pprContext theta, ptext SLIT("=>")]
+instance Outputable NewOrData where
+ ppr NewType = ptext SLIT("newtype")
+ ppr DataType = ptext SLIT("data")
\end{code}
-A type for recording what types a datatype should be specialised to.
-It's called a ``Sig'' because it's sort of like a ``type signature''
-for an datatype declaration.
-
-\begin{code}
-data SpecDataSig name
- = SpecDataSig name -- tycon to specialise
- (HsType name)
- SrcLoc
-
-instance (NamedThing name, Outputable name)
- => Outputable (SpecDataSig name) where
-
- ppr (SpecDataSig tycon ty _)
- = hsep [text "{-# SPECIALIZE data", ppr ty, text "#-}"]
-\end{code}
%************************************************************************
%* *
%************************************************************************
\begin{code}
-data ConDecl name
- = ConDecl name -- Constructor name
- (Context name) -- Existential context for this constructor
- (ConDetails name)
- SrcLoc
+type LConDecl name = Located (ConDecl name)
-data ConDetails name
- = VanillaCon -- prefix-style con decl
- [BangType name]
+-- data T b = forall a. Eq a => MkT a b
+-- MkT :: forall b a. Eq a => MkT a b
- | InfixCon -- infix-style con decl
- (BangType name)
- (BangType name)
+-- data T b where
+-- MkT1 :: Int -> T Int
- | RecCon -- record-style con decl
- [([name], BangType name)] -- list of "fields"
+-- data T = Int `MkT` Int
+-- | MkT2
- | NewCon -- newtype con decl
- (HsType name)
+-- data T a where
+-- Int `MkT` Int :: T Int
-data BangType name
- = Banged (HsType name) -- HsType: to allow Haskell extensions
- | Unbanged (HsType name) -- (MonoType only needed for straight Haskell)
-\end{code}
+data ConDecl name
+ = ConDecl
+ { con_name :: Located name -- Constructor name; this is used for the
+ -- DataCon itself, and for the user-callable wrapper Id
-\begin{code}
-instance (NamedThing name, Outputable name) => Outputable (ConDecl name) where
- ppr (ConDecl con cxt con_details loc)
- = pp_context_and_arrow cxt <+> ppr_con_details con con_details
+ , con_explicit :: HsExplicitForAll -- Is there an user-written forall? (cf. HStypes.HsForAllTy)
-ppr_con_details con (InfixCon ty1 ty2)
- = hsep [ppr_bang ty1, ppr con, ppr_bang ty2]
+ , con_qvars :: [LHsTyVarBndr name] -- ResTyH98: the constructor's existential type variables
+ -- ResTyGADT: all the constructor's quantified type variables
-ppr_con_details con (VanillaCon tys)
- = ppr con <+> hsep (map (ppr_bang) tys)
+ , con_cxt :: LHsContext name -- The context. This *does not* include the
+ -- "stupid theta" which lives only in the TyData decl
-ppr_con_details con (NewCon ty)
- = ppr con <+> pprParendHsType ty
+ , con_details :: HsConDetails name (LBangType name) -- The main payload
-ppr_con_details con (RecCon fields)
- = ppr con <+> braces (hsep (punctuate comma (map ppr_field fields)))
- where
- ppr_field (ns, ty) = hsep (map (ppr) ns) <+>
- ptext SLIT("::") <+>
- ppr_bang ty
+ , con_res :: ResType name -- Result type of the constructor
+ }
-ppr_bang (Banged ty) = ptext SLIT("!") <> pprParendHsType ty
-ppr_bang (Unbanged ty) = pprParendHsType ty
+data ResType name
+ = ResTyH98 -- Constructor was declared using Haskell 98 syntax
+ | ResTyGADT (LHsType name) -- Constructor was declared using GADT-style syntax,
+ -- and here is its result type
\end{code}
-%************************************************************************
-%* *
-\subsection[ClassDecl]{A class declaration}
-%* *
-%************************************************************************
-
\begin{code}
-data ClassDecl flexi name pat
- = ClassDecl (Context name) -- context...
- name -- name of the class
- [HsTyVar name] -- the class type variables
- [Sig name] -- methods' signatures
- (MonoBinds flexi name pat) -- default methods
- (ClassPragmas name)
- name name -- The names of the tycon and datacon for this class
- -- These are filled in by the renamer
- SrcLoc
+conDeclsNames :: Eq name => [ConDecl name] -> [Located name]
+ -- See tyClDeclNames for what this does
+ -- The function is boringly complicated because of the records
+ -- And since we only have equality, we have to be a little careful
+conDeclsNames cons
+ = snd (foldl do_one ([], []) cons)
+ where
+ do_one (flds_seen, acc) (ConDecl { con_name = lname, con_details = RecCon flds })
+ = (map unLoc new_flds ++ flds_seen, lname : [f | f <- new_flds] ++ acc)
+ where
+ new_flds = [ f | (f,_) <- flds, not (unLoc f `elem` flds_seen) ]
+
+ do_one (flds_seen, acc) c
+ = (flds_seen, (con_name c):acc)
+
+conDetailsTys details = map getBangType (hsConArgs details)
\end{code}
+
\begin{code}
-instance (NamedThing name, Outputable name, Outputable pat)
- => Outputable (ClassDecl flexi name pat) where
+instance (OutputableBndr name) => Outputable (ConDecl name) where
+ ppr = pprConDecl
- ppr (ClassDecl context clas tyvars sigs methods pragmas _ _ src_loc)
- | null sigs -- No "where" part
- = top_matter
+pprConDecl (ConDecl con expl tvs cxt details ResTyH98)
+ = sep [pprHsForAll expl tvs cxt, ppr_details con details]
+ where
+ ppr_details con (InfixCon t1 t2) = hsep [ppr t1, pprHsVar con, ppr t2]
+ ppr_details con (PrefixCon tys) = hsep (pprHsVar con : map ppr tys)
+ ppr_details con (RecCon fields) = ppr con <+> ppr_fields fields
- | otherwise -- Laid out
- = sep [hsep [top_matter, ptext SLIT("where {")],
- nest 4 (vcat [sep (map ppr_sig sigs),
- ppr methods,
- char '}'])]
- where
- top_matter = hsep [ptext SLIT("class"), pp_context_and_arrow context,
- ppr clas, hsep (map (ppr) tyvars)]
- ppr_sig sig = ppr sig <> semi
+pprConDecl (ConDecl con expl tvs cxt details (ResTyGADT res_ty))
+ = sep [pprHsForAll expl tvs cxt, ppr con <+> ppr_details details]
+ where
+ ppr_details (PrefixCon arg_tys) = dcolon <+> ppr (foldr mk_fun_ty res_ty arg_tys)
+ ppr_details (RecCon fields) = ppr fields <+> dcolon <+> ppr res_ty
+ ppr_details (PrefixCon _) = pprPanic "pprConDecl" (ppr con)
+
+ mk_fun_ty a b = noLoc (HsFunTy a b)
+
+ppr_fields fields = braces (sep (punctuate comma (map ppr_field fields)))
+ppr_field (n, ty) = ppr n <+> dcolon <+> ppr ty
\end{code}
%************************************************************************
%************************************************************************
\begin{code}
-data InstDecl flexi name pat
- = InstDecl (HsType name) -- Context => Class Instance-type
+type LInstDecl name = Located (InstDecl name)
+
+data InstDecl name
+ = InstDecl (LHsType name) -- Context => Class Instance-type
-- Using a polytype means that the renamer conveniently
-- figures out the quantified type variables for us.
+ (LHsBinds name)
+ [LSig name] -- User-supplied pragmatic info
- (MonoBinds flexi name pat)
-
- [Sig name] -- User-supplied pragmatic info
-
- (Maybe name) -- Name for the dictionary function
+instance (OutputableBndr name) => Outputable (InstDecl name) where
- SrcLoc
-\end{code}
-
-\begin{code}
-instance (NamedThing name, Outputable name, Outputable pat)
- => Outputable (InstDecl flexi name pat) where
-
- ppr (InstDecl inst_ty binds uprags dfun_name src_loc)
- = getPprStyle $ \ sty ->
- if ifaceStyle sty || (nullMonoBinds binds && null uprags) then
- hsep [ptext SLIT("instance"), ppr inst_ty]
- else
- vcat [hsep [ptext SLIT("instance"), ppr inst_ty, ptext SLIT("where")],
- nest 4 (ppr uprags),
- nest 4 (ppr binds) ]
+ ppr (InstDecl inst_ty binds uprags)
+ = vcat [hsep [ptext SLIT("instance"), ppr inst_ty, ptext SLIT("where")],
+ nest 4 (ppr uprags),
+ nest 4 (pprLHsBinds binds) ]
\end{code}
-
%************************************************************************
%* *
\subsection[DefaultDecl]{A @default@ declaration}
syntax, and that restriction must be checked in the front end.
\begin{code}
+type LDefaultDecl name = Located (DefaultDecl name)
+
data DefaultDecl name
- = DefaultDecl [HsType name]
- SrcLoc
+ = DefaultDecl [LHsType name]
-instance (NamedThing name, Outputable name)
+instance (OutputableBndr name)
=> Outputable (DefaultDecl name) where
- ppr (DefaultDecl tys src_loc)
+ ppr (DefaultDecl tys)
= ptext SLIT("default") <+> parens (interpp'SP tys)
\end{code}
%************************************************************************
\begin{code}
-data ForeignDecl name =
- ForeignDecl
- name
- ForKind
- (HsType name)
- ExtName
- CallConv
- SrcLoc
-
-instance (NamedThing name, Outputable name)
- => Outputable (ForeignDecl name) where
-
- ppr (ForeignDecl nm imp_exp ty ext_name cconv src_loc)
- = ptext SLIT("foreign") <+> ppr_imp_exp <+> pprCallConv cconv <+>
- ppr ext_name <+> ppr_unsafe <+> ppr nm <+> ptext SLIT("::") <+> ppr ty
- where
- (ppr_imp_exp, ppr_unsafe) =
- case imp_exp of
- FoLabel -> (ptext SLIT("label"), empty)
- FoExport -> (ptext SLIT("export"), empty)
- FoImport us
- | us -> (ptext SLIT("import"), ptext SLIT("unsafe"))
- | otherwise -> (ptext SLIT("import"), empty)
-
-data ForKind
- = FoLabel
- | FoExport
- | FoImport Bool -- True => unsafe call.
-
-data ExtName
- = Dynamic
- | ExtName FAST_STRING (Maybe FAST_STRING)
-
-isDynamic :: ExtName -> Bool
-isDynamic Dynamic = True
-isDynamic _ = False
-
-
-instance Outputable ExtName where
- ppr Dynamic = ptext SLIT("dynamic")
- ppr (ExtName nm mb_mod) =
- case mb_mod of { Nothing -> empty; Just m -> doubleQuotes (ptext m) } <+>
- doubleQuotes (ptext nm)
+-- foreign declarations are distinguished as to whether they define or use a
+-- Haskell name
+--
+-- * the Boolean value indicates whether the pre-standard deprecated syntax
+-- has been used
+--
+type LForeignDecl name = Located (ForeignDecl name)
+
+data ForeignDecl name
+ = ForeignImport (Located name) (LHsType name) ForeignImport Bool -- defines name
+ | ForeignExport (Located name) (LHsType name) ForeignExport Bool -- uses name
+
+-- specification of an imported external entity in dependence on the calling
+-- convention
+--
+data ForeignImport = -- import of a C entity
+ --
+ -- * the two strings specifying a header file or library
+ -- may be empty, which indicates the absence of a
+ -- header or object specification (both are not used
+ -- in the case of `CWrapper' and when `CFunction'
+ -- has a dynamic target)
+ --
+ -- * the calling convention is irrelevant for code
+ -- generation in the case of `CLabel', but is needed
+ -- for pretty printing
+ --
+ -- * `Safety' is irrelevant for `CLabel' and `CWrapper'
+ --
+ CImport CCallConv -- ccall or stdcall
+ Safety -- safe or unsafe
+ FastString -- name of C header
+ FastString -- name of library object
+ CImportSpec -- details of the C entity
+
+ -- import of a .NET function
+ --
+ | DNImport DNCallSpec
+
+-- details of an external C entity
+--
+data CImportSpec = CLabel CLabelString -- import address of a C label
+ | CFunction CCallTarget -- static or dynamic function
+ | CWrapper -- wrapper to expose closures
+ -- (former f.e.d.)
+
+-- specification of an externally exported entity in dependence on the calling
+-- convention
+--
+data ForeignExport = CExport CExportSpec -- contains the calling convention
+ | DNExport -- presently unused
+
+-- abstract type imported from .NET
+--
+data FoType = DNType -- In due course we'll add subtype stuff
+ deriving (Eq) -- Used for equality instance for TyClDecl
+
+
+-- pretty printing of foreign declarations
+--
+
+instance OutputableBndr name => Outputable (ForeignDecl name) where
+ ppr (ForeignImport n ty fimport _) =
+ ptext SLIT("foreign import") <+> ppr fimport <+>
+ ppr n <+> dcolon <+> ppr ty
+ ppr (ForeignExport n ty fexport _) =
+ ptext SLIT("foreign export") <+> ppr fexport <+>
+ ppr n <+> dcolon <+> ppr ty
+
+instance Outputable ForeignImport where
+ ppr (DNImport spec) =
+ ptext SLIT("dotnet") <+> ppr spec
+ ppr (CImport cconv safety header lib spec) =
+ ppr cconv <+> ppr safety <+>
+ char '"' <> pprCEntity header lib spec <> char '"'
+ where
+ pprCEntity header lib (CLabel lbl) =
+ ptext SLIT("static") <+> ftext header <+> char '&' <>
+ pprLib lib <> ppr lbl
+ pprCEntity header lib (CFunction (StaticTarget lbl)) =
+ ptext SLIT("static") <+> ftext header <+> char '&' <>
+ pprLib lib <> ppr lbl
+ pprCEntity header lib (CFunction (DynamicTarget)) =
+ ptext SLIT("dynamic")
+ pprCEntity _ _ (CWrapper) = ptext SLIT("wrapper")
+ --
+ pprLib lib | nullFS lib = empty
+ | otherwise = char '[' <> ppr lib <> char ']'
+
+instance Outputable ForeignExport where
+ ppr (CExport (CExportStatic lbl cconv)) =
+ ppr cconv <+> char '"' <> ppr lbl <> char '"'
+ ppr (DNExport ) =
+ ptext SLIT("dotnet") <+> ptext SLIT("\"<unused>\"")
+
+instance Outputable FoType where
+ ppr DNType = ptext SLIT("type dotnet")
\end{code}
+
%************************************************************************
%* *
-\subsection{Signatures in interface files}
+\subsection{Transformation rules}
%* *
%************************************************************************
\begin{code}
-data IfaceSig name
- = IfaceSig name
- (HsType name)
- [HsIdInfo name]
- SrcLoc
-
-instance (NamedThing name, Outputable name) => Outputable (IfaceSig name) where
- ppr (IfaceSig var ty _ _)
- = hang (hsep [ppr var, ptext SLIT("::")])
- 4 (ppr ty)
-
-data HsIdInfo name
- = HsArity ArityInfo
- | HsStrictness (HsStrictnessInfo name)
- | HsUnfold Bool (UfExpr name) -- True <=> INLINE pragma
- | HsUpdate UpdateInfo
- | HsArgUsage ArgUsageInfo
- | HsFBType FBTypeInfo
- | HsSpecialise [HsTyVar name] [HsType name] (UfExpr name)
-
-
-data HsStrictnessInfo name
- = HsStrictnessInfo [Demand]
- (Maybe (name, [name])) -- Worker, if any
- -- and needed constructors
- | HsBottom
+type LRuleDecl name = Located (RuleDecl name)
+
+data RuleDecl name
+ = HsRule -- Source rule
+ RuleName -- Rule name
+ Activation
+ [RuleBndr name] -- Forall'd vars; after typechecking this includes tyvars
+ (Located (HsExpr name)) -- LHS
+ (Located (HsExpr name)) -- RHS
+
+data RuleBndr name
+ = RuleBndr (Located name)
+ | RuleBndrSig (Located name) (LHsType name)
+
+collectRuleBndrSigTys :: [RuleBndr name] -> [LHsType name]
+collectRuleBndrSigTys bndrs = [ty | RuleBndrSig _ ty <- bndrs]
+
+instance OutputableBndr name => Outputable (RuleDecl name) where
+ ppr (HsRule name act ns lhs rhs)
+ = sep [text "{-# RULES" <+> doubleQuotes (ftext name) <+> ppr act,
+ nest 4 (pp_forall <+> pprExpr (unLoc lhs)),
+ nest 4 (equals <+> pprExpr (unLoc rhs) <+> text "#-}") ]
+ where
+ pp_forall | null ns = empty
+ | otherwise = text "forall" <+> fsep (map ppr ns) <> dot
+
+instance OutputableBndr name => Outputable (RuleBndr name) where
+ ppr (RuleBndr name) = ppr name
+ ppr (RuleBndrSig name ty) = ppr name <> dcolon <> ppr ty
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection[DeprecDecl]{Deprecations}
+%* *
+%************************************************************************
+
+We use exported entities for things to deprecate.
+
+\begin{code}
+type LDeprecDecl name = Located (DeprecDecl name)
+
+data DeprecDecl name = Deprecation name DeprecTxt
+
+instance OutputableBndr name => Outputable (DeprecDecl name) where
+ ppr (Deprecation thing txt)
+ = hsep [text "{-# DEPRECATED", ppr thing, doubleQuotes (ppr txt), text "#-}"]
\end{code}
projects / ghc-hetmet.git / blobdiff