%
-% (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@,
-@InstDecl@, @DefaultDecl@.
+Definitions for: @TyDecl@ and @oCnDecl@, @ClassDecl@,
+@InstDecl@, @DefaultDecl@ and @ForeignDecl@.
\begin{code}
-#include "HsVersions.h"
-
-module HsDecls where
+module HsDecls (
+ HsDecl(..), TyClDecl(..), InstDecl(..), RuleDecl(..), RuleBndr(..),
+ DefaultDecl(..),
+ ForeignDecl(..), FoImport(..), FoExport(..), FoType(..),
+ ConDecl(..), ConDetails(..),
+ BangType(..), getBangType, getBangStrictness, unbangedType,
+ DeprecDecl(..), DeprecTxt,
+ hsDeclName, instDeclName,
+ tyClDeclName, tyClDeclNames, tyClDeclSysNames, tyClDeclTyVars,
+ isClassDecl, isSynDecl, isDataDecl, isIfaceSigDecl, countTyClDecls,
+ mkClassDeclSysNames, isIfaceRuleDecl, ifaceRuleDeclName,
+ getClassDeclSysNames, conDetailsTys
+ ) where
-import Ubiq
+#include "HsVersions.h"
-- friends:
-import HsLoop ( nullMonoBinds, MonoBinds, Sig )
-import HsPragmas ( DataPragmas, ClassPragmas,
- InstancePragmas, ClassOpPragmas )
+import HsBinds ( HsBinds, MonoBinds, Sig(..), FixitySig(..) )
+import HsExpr ( HsExpr )
import HsTypes
+import PprCore ( pprCoreRule )
+import HsCore ( UfExpr, UfBinder, HsIdInfo, pprHsIdInfo,
+ eq_ufBinders, eq_ufExpr, pprUfExpr
+ )
+import CoreSyn ( CoreRule(..) )
+import BasicTypes ( NewOrData(..), StrictnessMark(..) )
+import ForeignCall ( CExportSpec, CCallSpec, DNCallSpec, CCallConv )
-- others:
-import Name ( pprSym, pprNonSym )
-import Outputable ( interppSP, interpp'SP,
- Outputable(..){-instance * []-}
- )
-import Pretty
+import Name ( NamedThing )
+import FunDeps ( pprFundeps )
+import Class ( FunDep, DefMeth(..) )
+import CStrings ( CLabelString )
+import Outputable
+import Util ( eqListBy )
import SrcLoc ( SrcLoc )
-import Util ( cmpList, panic#{-ToDo:rm eventually-} )
+import FastString
\end{code}
+
%************************************************************************
%* *
-\subsection[FixityDecl]{A fixity declaration}
+\subsection[HsDecl]{Declarations}
%* *
%************************************************************************
\begin{code}
-data FixityDecl name
- = InfixL name Int
- | InfixR name Int
- | InfixN name Int
+data HsDecl name pat
+ = TyClD (TyClDecl name pat)
+ | InstD (InstDecl name pat)
+ | DefD (DefaultDecl name)
+ | ValD (HsBinds name pat)
+ | ForD (ForeignDecl name)
+ | FixD (FixitySig name)
+ | DeprecD (DeprecDecl name)
+ | RuleD (RuleDecl name pat)
+
+-- NB: all top-level fixity decls are contained EITHER
+-- EITHER FixDs
+-- 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
\end{code}
\begin{code}
-instance (NamedThing name, Outputable name)
- => Outputable (FixityDecl name) where
- ppr sty (InfixL var prec) = print_it sty "l" prec var
- ppr sty (InfixR var prec) = print_it sty "r" prec var
- ppr sty (InfixN var prec) = print_it sty "" prec var
-
-print_it sty suff prec var
- = ppBesides [ppStr "infix", ppStr suff, ppSP, ppInt prec, ppSP, pprSym sty var]
+#ifdef DEBUG
+hsDeclName :: (NamedThing name, Outputable name, Outputable pat)
+ => HsDecl name pat -> name
+#endif
+hsDeclName (TyClD decl) = tyClDeclName decl
+hsDeclName (InstD decl) = instDeclName decl
+hsDeclName (ForD decl) = forDeclName decl
+hsDeclName (FixD (FixitySig name _ _)) = name
+-- Others don't make sense
+#ifdef DEBUG
+hsDeclName x = pprPanic "HsDecls.hsDeclName" (ppr x)
+#endif
+
+
+instDeclName :: InstDecl name pat -> name
+instDeclName (InstDecl _ _ _ (Just name) _) = name
+
\end{code}
+\begin{code}
+instance (NamedThing name, Outputable name, Outputable pat)
+ => Outputable (HsDecl name pat) 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
+ ppr (FixD fd) = ppr fd
+ ppr (RuleD rd) = ppr rd
+ ppr (DeprecD dd) = ppr dd
+\end{code}
+
+
%************************************************************************
%* *
\subsection[TyDecl]{@data@, @newtype@ or @type@ (synonym) type declaration}
%* *
%************************************************************************
-\begin{code}
-data TyDecl name
- = TyData (Context name) -- context
- name -- type constructor
- [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
-
- | TyNew (Context name) -- context
- name -- type constructor
- [name] -- type variables
- [ConDecl name] -- data constructor (empty if abstract)
- (Maybe [name]) -- derivings; as above
- (DataPragmas name)
- 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:
+ - Make up their occurrence names immediately
+ This is done in RdrHsSyn.mkClassDecl, mkTyDecl, mkConDecl
+
+ - Ensure they "point to" the parent data/class decl
+ when loading that decl from an interface file
+ (See RnHiFiles.getTyClDeclSysNames)
+
+ - When renaming the decl look them up in the name cache,
+ ensure correct module and provenance is set
+
+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 globalises 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
- | TySynonym name -- type constructor
- [name] -- type variables
- (MonoType name) -- synonym expansion
- SrcLoc
+\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
+
+data TyClDecl name pat
+ = IfaceSig { tcdName :: name, -- It may seem odd to classify an interface-file signature
+ tcdType :: HsType name, -- as a 'TyClDecl', but it's very convenient.
+ tcdIdInfo :: [HsIdInfo name],
+ tcdLoc :: SrcLoc
+ }
+
+ | ForeignType { tcdName :: name, -- See remarks about IfaceSig above
+ tcdExtName :: Maybe FastString,
+ tcdFoType :: FoType,
+ tcdLoc :: SrcLoc }
+
+ | TyData { tcdND :: NewOrData,
+ tcdCtxt :: HsContext name, -- context
+ tcdName :: name, -- type constructor
+ tcdTyVars :: [HsTyVarBndr name], -- type variables
+ tcdCons :: [ConDecl name], -- data constructors (empty if abstract)
+ tcdNCons :: Int, -- Number of data constructors (valid even if type is abstract)
+ tcdDerivs :: Maybe [name], -- derivings; Nothing => not specified
+ -- (i.e., derive default); Just [] => derive
+ -- *nothing*; Just <list> => as you would
+ -- expect...
+ tcdSysNames :: DataSysNames name, -- Generic converter functions
+ tcdLoc :: SrcLoc
+ }
+
+ | TySynonym { tcdName :: name, -- type constructor
+ tcdTyVars :: [HsTyVarBndr name], -- type variables
+ tcdSynRhs :: HsType name, -- synonym expansion
+ tcdLoc :: SrcLoc
+ }
+
+ | ClassDecl { tcdCtxt :: HsContext name, -- Context...
+ tcdName :: name, -- Name of the class
+ tcdTyVars :: [HsTyVarBndr name], -- The class type variables
+ tcdFDs :: [FunDep name], -- Functional dependencies
+ tcdSigs :: [Sig name], -- Methods' signatures
+ tcdMeths :: Maybe (MonoBinds name pat), -- Default methods
+ -- Nothing for imported class decls
+ -- Just bs for source class decls
+ tcdSysNames :: ClassSysNames name,
+ tcdLoc :: SrcLoc
+ }
\end{code}
+Simple classifiers
+
\begin{code}
-instance (NamedThing name, Outputable name)
- => Outputable (TyDecl name) where
+isIfaceSigDecl, isDataDecl, isSynDecl, isClassDecl :: TyClDecl name pat -> Bool
- ppr sty (TySynonym tycon tyvars mono_ty src_loc)
- = ppHang (pp_decl_head sty SLIT("type") ppNil tycon tyvars)
- 4 (ppCat [ppEquals, ppr sty mono_ty])
+isIfaceSigDecl (IfaceSig {}) = True
+isIfaceSigDecl other = False
- ppr sty (TyData context tycon tyvars condecls derivings pragmas src_loc)
- = pp_tydecl sty
- (pp_decl_head sty SLIT("data") (pprContext sty context) tycon tyvars)
- (pp_condecls sty condecls)
- derivings
+isSynDecl (TySynonym {}) = True
+isSynDecl other = False
- ppr sty (TyNew context tycon tyvars condecl derivings pragmas src_loc)
- = pp_tydecl sty
- (pp_decl_head sty SLIT("newtype") (pprContext sty context) tycon tyvars)
- (pp_condecls sty condecl)
- derivings
+isDataDecl (TyData {}) = True
+isDataDecl other = False
-pp_decl_head sty str pp_context tycon tyvars
- = ppCat [ppPStr str, pp_context, ppr sty tycon, interppSP sty tyvars]
+isClassDecl (ClassDecl {}) = True
+isClassDecl other = False
+\end{code}
-pp_condecls sty [] = ppNil -- abstract datatype
-pp_condecls sty (c:cs)
- = ppSep (ppBeside (ppStr "= ") (ppr sty c)
- : map (\ x -> ppBeside (ppStr "| ") (ppr sty x)) cs)
+Dealing with names
-pp_tydecl sty pp_head pp_decl_rhs derivings
- = ppHang pp_head 4 (ppSep [
- pp_decl_rhs,
- case derivings of
- Nothing -> ppNil
- Just ds -> ppBeside (ppPStr SLIT("deriving "))
- (ppParens (ppInterleave ppComma (map (ppr sty) ds)))])
+\begin{code}
+--------------------------------
+tyClDeclName :: TyClDecl name pat -> name
+tyClDeclName tycl_decl = tcdName tycl_decl
+
+--------------------------------
+tyClDeclNames :: Eq name => TyClDecl name pat -> [(name, SrcLoc)]
+-- 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 {tcdName = name, tcdLoc = loc}) = [(name,loc)]
+tyClDeclNames (IfaceSig {tcdName = name, tcdLoc = loc}) = [(name,loc)]
+tyClDeclNames (ForeignType {tcdName = name, tcdLoc = loc}) = [(name,loc)]
+
+tyClDeclNames (ClassDecl {tcdName = cls_name, tcdSigs = sigs, tcdLoc = loc})
+ = (cls_name,loc) : [(n,loc) | ClassOpSig n _ _ loc <- sigs]
+
+tyClDeclNames (TyData {tcdName = tc_name, tcdCons = cons, tcdLoc = loc})
+ = (tc_name,loc) : conDeclsNames cons
+
+
+tyClDeclTyVars (TySynonym {tcdTyVars = tvs}) = tvs
+tyClDeclTyVars (TyData {tcdTyVars = tvs}) = tvs
+tyClDeclTyVars (ClassDecl {tcdTyVars = tvs}) = tvs
+tyClDeclTyVars (ForeignType {}) = []
+tyClDeclTyVars (IfaceSig {}) = []
+
+
+--------------------------------
+-- The "system names" are extra implicit names *bound* by the decl.
+-- They are kept in a list rather than a tuple
+-- to make the renamer easier.
+
+type ClassSysNames name = [name]
+-- For class decls they are:
+-- [tycon, datacon wrapper, datacon worker,
+-- superclass selector 1, ..., superclass selector n]
+
+type DataSysNames name = [name]
+-- For data decls they are
+-- [from, to]
+-- where from :: T -> Tring
+-- to :: Tring -> T
+
+tyClDeclSysNames :: TyClDecl name pat -> [(name, SrcLoc)]
+-- Similar to tyClDeclNames, but returns the "implicit"
+-- or "system" names of the declaration
+
+tyClDeclSysNames (ClassDecl {tcdSysNames = names, tcdLoc = loc})
+ = [(n,loc) | n <- names]
+tyClDeclSysNames (TyData {tcdCons = cons, tcdSysNames = names, tcdLoc = loc})
+ = [(n,loc) | n <- names] ++
+ [(wkr_name,loc) | ConDecl _ wkr_name _ _ _ loc <- cons]
+tyClDeclSysNames decl = []
+
+
+mkClassDeclSysNames :: (name, name, name, [name]) -> [name]
+getClassDeclSysNames :: [name] -> (name, name, name, [name])
+mkClassDeclSysNames (a,b,c,ds) = a:b:c:ds
+getClassDeclSysNames (a:b:c:ds) = (a,b,c,ds)
\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}
+instance (NamedThing name, Ord name) => Eq (TyClDecl name pat) where
+ -- Used only when building interface files
+ (==) d1@(IfaceSig {}) d2@(IfaceSig {})
+ = tcdName d1 == tcdName d2 &&
+ tcdType d1 == tcdType d2 &&
+ tcdIdInfo d1 == tcdIdInfo d2
+
+ (==) d1@(ForeignType {}) d2@(ForeignType {})
+ = tcdName d1 == tcdName d2 &&
+ tcdFoType d1 == tcdFoType d2
+
+ (==) d1@(TyData {}) d2@(TyData {})
+ = tcdName d1 == tcdName d2 &&
+ tcdND d1 == tcdND d2 &&
+ eqWithHsTyVars (tcdTyVars d1) (tcdTyVars d2) (\ env ->
+ eq_hsContext env (tcdCtxt d1) (tcdCtxt d2) &&
+ eqListBy (eq_ConDecl env) (tcdCons d1) (tcdCons d2)
+ )
+
+ (==) d1@(TySynonym {}) d2@(TySynonym {})
+ = tcdName d1 == tcdName d2 &&
+ eqWithHsTyVars (tcdTyVars d1) (tcdTyVars d2) (\ env ->
+ eq_hsType env (tcdSynRhs d1) (tcdSynRhs d2)
+ )
+
+ (==) d1@(ClassDecl {}) d2@(ClassDecl {})
+ = tcdName d1 == tcdName d2 &&
+ eqWithHsTyVars (tcdTyVars d1) (tcdTyVars d2) (\ env ->
+ eq_hsContext env (tcdCtxt d1) (tcdCtxt d2) &&
+ eqListBy (eq_hsFD env) (tcdFDs d1) (tcdFDs d2) &&
+ eqListBy (eq_cls_sig env) (tcdSigs d1) (tcdSigs d2)
+ )
+
+ (==) _ _ = False -- default case
+
+eq_hsFD env (ns1,ms1) (ns2,ms2)
+ = eqListBy (eq_hsVar env) ns1 ns2 && eqListBy (eq_hsVar env) ms1 ms2
+
+eq_cls_sig env (ClassOpSig n1 dm1 ty1 _) (ClassOpSig n2 dm2 ty2 _)
+ = n1==n2 && dm1 `eq_dm` dm2 && eq_hsType env ty1 ty2
+ where
+ -- Ignore the name of the default method for (DefMeth id)
+ -- This is used for comparing declarations before putting
+ -- them into interface files, and the name of the default
+ -- method isn't relevant
+ NoDefMeth `eq_dm` NoDefMeth = True
+ GenDefMeth `eq_dm` GenDefMeth = True
+ DefMeth _ `eq_dm` DefMeth _ = True
+ dm1 `eq_dm` dm2 = False
+
+
+\end{code}
\begin{code}
-data SpecDataSig name
- = SpecDataSig name -- tycon to specialise
- (MonoType name)
- SrcLoc
+countTyClDecls :: [TyClDecl name pat] -> (Int, Int, Int, Int, Int)
+ -- class, data, newtype, synonym decls
+countTyClDecls decls
+ = (length [() | ClassDecl {} <- decls],
+ length [() | TySynonym {} <- decls],
+ length [() | IfaceSig {} <- decls],
+ length [() | TyData {tcdND = DataType} <- decls],
+ length [() | TyData {tcdND = NewType} <- decls])
+\end{code}
+
+\begin{code}
+instance (NamedThing name, Outputable name, Outputable pat)
+ => Outputable (TyClDecl name pat) where
-instance (NamedThing name, Outputable name)
- => Outputable (SpecDataSig name) where
+ ppr (IfaceSig {tcdName = var, tcdType = ty, tcdIdInfo = info})
+ = hsep [ppr var, dcolon, ppr ty, pprHsIdInfo info]
- ppr sty (SpecDataSig tycon ty _)
- = ppCat [ppStr "{-# SPECIALIZE data", ppr sty ty, ppStr "#-}"]
+ ppr (ForeignType {tcdName = tycon})
+ = hsep [ptext SLIT("foreign import type dotnet"), ppr tycon]
+
+ ppr (TySynonym {tcdName = tycon, tcdTyVars = tyvars, tcdSynRhs = mono_ty})
+ = hang (ptext SLIT("type") <+> pp_decl_head [] tycon tyvars <+> equals)
+ 4 (ppr mono_ty)
+
+ ppr (TyData {tcdND = new_or_data, tcdCtxt = context, tcdName = tycon,
+ tcdTyVars = tyvars, tcdCons = condecls, tcdNCons = ncons,
+ tcdDerivs = derivings})
+ = pp_tydecl (ptext keyword <+> pp_decl_head context tycon tyvars)
+ (pp_condecls condecls ncons)
+ derivings
+ where
+ keyword = case new_or_data of
+ NewType -> SLIT("newtype")
+ DataType -> SLIT("data")
+
+ ppr (ClassDecl {tcdCtxt = context, tcdName = clas, tcdTyVars = tyvars, tcdFDs = fds,
+ tcdSigs = sigs, tcdMeths = methods})
+ | null sigs -- No "where" part
+ = top_matter
+
+ | otherwise -- Laid out
+ = sep [hsep [top_matter, ptext SLIT("where {")],
+ nest 4 (sep [sep (map ppr_sig sigs), pp_methods, char '}'])]
+ where
+ top_matter = ptext SLIT("class") <+> pp_decl_head context clas tyvars <+> pprFundeps fds
+ ppr_sig sig = ppr sig <> semi
+ pp_methods = getPprStyle $ \ sty ->
+ if ifaceStyle sty then empty else ppr methods
+
+pp_decl_head :: Outputable name => HsContext name -> name -> [HsTyVarBndr name] -> SDoc
+pp_decl_head context thing tyvars = hsep [pprHsContext context, ppr thing, interppSP tyvars]
+
+pp_condecls [] ncons = ptext SLIT("{- abstract with") <+> int ncons <+> ptext SLIT("constructors -}")
+pp_condecls (c:cs) ncons = equals <+> sep (ppr c : map (\ c -> ptext SLIT("|") <+> ppr c) cs)
+
+pp_tydecl pp_head pp_decl_rhs derivings
+ = hang pp_head 4 (sep [
+ pp_decl_rhs,
+ case derivings of
+ Nothing -> empty
+ Just ds -> hsep [ptext SLIT("deriving"), parens (interpp'SP ds)]
+ ])
\end{code}
+
%************************************************************************
%* *
\subsection[ConDecl]{A data-constructor declaration}
\begin{code}
data ConDecl name
- = ConDecl name -- prefix-style con decl
- [BangType name]
- SrcLoc
+ = ConDecl name -- Constructor name; this is used for the
+ -- DataCon itself, and for the user-callable wrapper Id
- | ConOpDecl (BangType name) -- infix-style con decl
- name
- (BangType name)
- SrcLoc
+ name -- Name of the constructor's 'worker Id'
+ -- Filled in as the ConDecl is built
- | RecConDecl name
- [([name], BangType name)] -- list of "fields"
- SrcLoc
+ [HsTyVarBndr name] -- Existentially quantified type variables
+ (HsContext name) -- ...and context
+ -- If both are empty then there are no existentials
- | NewConDecl name -- newtype con decl
- (MonoType name)
+ (ConDetails name)
SrcLoc
-data BangType name
- = Banged (MonoType name)
- | Unbanged (MonoType name)
+data ConDetails name
+ = VanillaCon -- prefix-style con decl
+ [BangType name]
+
+ | InfixCon -- infix-style con decl
+ (BangType name)
+ (BangType name)
+
+ | RecCon -- record-style con decl
+ [([name], BangType name)] -- list of "fields"
\end{code}
\begin{code}
-instance (NamedThing name, Outputable name) => Outputable (ConDecl name) where
-
- ppr sty (ConDecl con tys _)
- = ppCat [pprNonSym sty con, ppInterleave ppNil (map (ppr_bang sty) tys)]
- ppr sty (ConOpDecl ty1 op ty2 _)
- = ppCat [ppr_bang sty ty1, pprSym sty op, ppr_bang sty ty2]
- ppr sty (NewConDecl con ty _)
- = ppCat [pprNonSym sty con, pprParendMonoType sty ty]
- ppr sty (RecConDecl con fields _)
- = ppCat [pprNonSym sty con, ppChar '{',
- ppInterleave pp'SP (map pp_field fields), ppChar '}']
- where
- pp_field (n, ty) = ppCat [ppr sty n, ppPStr SLIT("::"), ppr_bang sty ty]
+conDeclsNames :: Eq name => [ConDecl name] -> [(name,SrcLoc)]
+ -- 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 name _ _ _ details loc)
+ = do_details ((name,loc):acc) details
+ where
+ do_details acc (RecCon flds) = foldl do_fld (flds_seen, acc) flds
+ do_details acc other = (flds_seen, acc)
+
+ do_fld acc (flds, _) = foldl do_fld1 acc flds
+
+ do_fld1 (flds_seen, acc) fld
+ | fld `elem` flds_seen = (flds_seen,acc)
+ | otherwise = (fld:flds_seen, (fld,loc):acc)
+\end{code}
-ppr_bang sty (Banged ty) = ppBeside (ppChar '!') (pprParendMonoType sty ty)
-ppr_bang sty (Unbanged ty) = pprParendMonoType sty ty
+\begin{code}
+conDetailsTys :: ConDetails name -> [HsType name]
+conDetailsTys (VanillaCon btys) = map getBangType btys
+conDetailsTys (InfixCon bty1 bty2) = [getBangType bty1, getBangType bty2]
+conDetailsTys (RecCon fields) = [getBangType bty | (_, bty) <- fields]
+
+
+eq_ConDecl env (ConDecl n1 _ tvs1 cxt1 cds1 _)
+ (ConDecl n2 _ tvs2 cxt2 cds2 _)
+ = n1 == n2 &&
+ (eq_hsTyVars env tvs1 tvs2 $ \ env ->
+ eq_hsContext env cxt1 cxt2 &&
+ eq_ConDetails env cds1 cds2)
+
+eq_ConDetails env (VanillaCon bts1) (VanillaCon bts2)
+ = eqListBy (eq_btype env) bts1 bts2
+eq_ConDetails env (InfixCon bta1 btb1) (InfixCon bta2 btb2)
+ = eq_btype env bta1 bta2 && eq_btype env btb1 btb2
+eq_ConDetails env (RecCon fs1) (RecCon fs2)
+ = eqListBy (eq_fld env) fs1 fs2
+eq_ConDetails env _ _ = False
+
+eq_fld env (ns1,bt1) (ns2, bt2) = ns1==ns2 && eq_btype env bt1 bt2
\end{code}
+
+\begin{code}
+data BangType name = BangType StrictnessMark (HsType name)
-%************************************************************************
-%* *
-\subsection[ClassDecl]{A class declaration}
-%* *
-%************************************************************************
+getBangType (BangType _ ty) = ty
+getBangStrictness (BangType s _) = s
-\begin{code}
-data ClassDecl tyvar uvar name pat
- = ClassDecl (Context name) -- context...
- name -- name of the class
- name -- the class type variable
- [Sig name] -- methods' signatures
- (MonoBinds tyvar uvar name pat) -- default methods
- (ClassPragmas name)
- SrcLoc
+unbangedType ty = BangType NotMarkedStrict ty
+
+eq_btype env (BangType s1 t1) (BangType s2 t2) = s1==s2 && eq_hsType env t1 t2
\end{code}
\begin{code}
-instance (NamedThing name, Outputable name, Outputable pat,
- Eq tyvar, Outputable tyvar, Eq uvar, Outputable uvar)
- => Outputable (ClassDecl tyvar uvar name pat) where
-
- ppr sty (ClassDecl context clas tyvar sigs methods pragmas src_loc)
- = let
- top_matter = ppCat [ppStr "class", pprContext sty context,
- ppr sty clas, ppr sty tyvar]
- in
- if null sigs && nullMonoBinds methods then
- ppAbove top_matter (ppNest 4 (ppr sty pragmas))
- else
- ppAboves [ppCat [top_matter, ppStr "where"],
- ppNest 4 (ppAboves (map (ppr sty) sigs)),
- ppNest 4 (ppr sty methods),
- ppNest 4 (ppr sty pragmas) ]
+instance (Outputable name) => Outputable (ConDecl name) where
+ ppr (ConDecl con _ tvs cxt con_details loc)
+ = sep [pprHsForAll tvs cxt, ppr_con_details con con_details]
+
+ppr_con_details con (InfixCon ty1 ty2)
+ = hsep [ppr_bang ty1, ppr con, ppr_bang ty2]
+
+ppr_con_details con (VanillaCon tys)
+ = ppr con <+> hsep (map (ppr_bang) tys)
+
+ppr_con_details con (RecCon fields)
+ = ppr con <+> braces (sep (punctuate comma (map ppr_field fields)))
+ where
+ ppr_field (ns, ty) = hsep (map (ppr) ns) <+>
+ dcolon <+>
+ ppr_bang ty
+
+instance Outputable name => Outputable (BangType name) where
+ ppr = ppr_bang
+
+ppr_bang (BangType s ty) = ppr s <> pprParendHsType ty
\end{code}
+
%************************************************************************
%* *
-\subsection[InstDecl]{An instance declaration (also, @SpecInstSig@)}
+\subsection[InstDecl]{An instance declaration
%* *
%************************************************************************
\begin{code}
-data InstDecl tyvar uvar name pat
- = InstDecl name -- Class
-
- (PolyType name) -- Context => Instance-type
+data InstDecl name pat
+ = InstDecl (HsType name) -- Context => Class Instance-type
-- Using a polytype means that the renamer conveniently
-- figures out the quantified type variables for us.
- (MonoBinds tyvar uvar name pat)
+ (MonoBinds name pat)
- Bool -- True <=> This instance decl is from the
- -- module being compiled; False <=> It is from
- -- an imported interface.
+ [Sig name] -- User-supplied pragmatic info
- (Maybe Module) -- The name of the module where the instance decl
- -- originally came from; Nothing => Prelude
+ (Maybe name) -- Name for the dictionary function
+ -- Nothing for source-file instance decls
- [Sig name] -- actually user-supplied pragmatic info
- (InstancePragmas name) -- interface-supplied pragmatic info
SrcLoc
\end{code}
\begin{code}
-instance (NamedThing name, Outputable name, Outputable pat,
- Eq tyvar, Outputable tyvar, Eq uvar, Outputable uvar)
- => Outputable (InstDecl tyvar uvar name pat) where
-
- ppr sty (InstDecl clas ty binds local modname uprags pragmas src_loc)
- = let
- (context, inst_ty)
- = case ty of
- HsPreForAllTy c t -> (c, t)
- HsForAllTy _ c t -> (c, t)
-
- top_matter = ppCat [ppStr "instance", pprContext sty context,
- ppr sty clas, pprParendMonoType sty inst_ty]
- in
- if nullMonoBinds binds && null uprags then
- ppAbove top_matter (ppNest 4 (ppr sty pragmas))
+instance (Outputable name, Outputable pat)
+ => Outputable (InstDecl name pat) where
+
+ ppr (InstDecl inst_ty binds uprags maybe_dfun_name src_loc)
+ = getPprStyle $ \ sty ->
+ if ifaceStyle sty then
+ hsep [ptext SLIT("instance"), ppr inst_ty, equals, pp_dfun]
else
- ppAboves [ppCat [top_matter, ppStr "where"],
- if null uprags then ppNil else ppNest 4 (ppr sty uprags),
- ppNest 4 (ppr sty binds),
- ppNest 4 (ppr sty pragmas) ]
+ vcat [hsep [ptext SLIT("instance"), ppr inst_ty, ptext SLIT("where")],
+ nest 4 (ppr uprags),
+ nest 4 (ppr binds) ]
+ where
+ pp_dfun = case maybe_dfun_name of
+ Just df -> ppr df
+ Nothing -> empty
\end{code}
-A type for recording what instances the user wants to specialise;
-called a ``Sig'' because it's sort of like a ``type signature'' for an
-instance.
\begin{code}
-data SpecInstSig name
- = SpecInstSig name -- class
- (MonoType name) -- type to specialise to
- SrcLoc
-
-instance (NamedThing name, Outputable name)
- => Outputable (SpecInstSig name) where
-
- ppr sty (SpecInstSig clas ty _)
- = ppCat [ppStr "{-# SPECIALIZE instance", ppr sty clas, ppr sty ty, ppStr "#-}"]
+instance Ord name => Eq (InstDecl name pat) where
+ -- Used for interface comparison only, so don't compare bindings
+ (==) (InstDecl inst_ty1 _ _ dfun1 _) (InstDecl inst_ty2 _ _ dfun2 _)
+ = inst_ty1 == inst_ty2 && dfun1 == dfun2
\end{code}
+
%************************************************************************
%* *
\subsection[DefaultDecl]{A @default@ declaration}
\begin{code}
data DefaultDecl name
- = DefaultDecl [MonoType name]
+ = DefaultDecl [HsType name]
SrcLoc
-instance (NamedThing name, Outputable name)
+instance (Outputable name)
=> Outputable (DefaultDecl name) where
- ppr sty (DefaultDecl tys src_loc)
- = ppBeside (ppPStr SLIT("default ")) (ppParens (interpp'SP sty tys))
+ ppr (DefaultDecl tys src_loc)
+ = ptext SLIT("default") <+> parens (interpp'SP tys)
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{Foreign function interface declaration}
+%* *
+%************************************************************************
+
+\begin{code}
+data ForeignDecl name
+ = ForeignImport name (HsType name) FoImport SrcLoc
+ | ForeignExport name (HsType name) FoExport SrcLoc
+
+forDeclName (ForeignImport n _ _ _) = n
+forDeclName (ForeignExport n _ _ _) = n
+
+data FoImport
+ = LblImport CLabelString -- foreign label
+ | CImport CCallSpec -- foreign import
+ | CDynImport CCallConv -- foreign export dynamic
+ | DNImport DNCallSpec -- foreign import dotnet
+
+data FoExport = CExport CExportSpec
+
+data FoType = DNType -- In due course we'll add subtype stuff
+ deriving( Eq ) -- Used for equality instance for TyClDecl
+
+instance Outputable name => Outputable (ForeignDecl name) where
+ ppr (ForeignImport nm ty (LblImport lbl) src_loc)
+ = ptext SLIT("foreign label") <+> ppr lbl <+> ppr nm <+> dcolon <+> ppr ty
+ ppr (ForeignImport nm ty decl src_loc)
+ = ptext SLIT("foreign import") <+> ppr decl <+> ppr nm <+> dcolon <+> ppr ty
+ ppr (ForeignExport nm ty decl src_loc)
+ = ptext SLIT("foreign export") <+> ppr decl <+> ppr nm <+> dcolon <+> ppr ty
+
+instance Outputable FoImport where
+ ppr (CImport d) = ppr d
+ ppr (CDynImport conv) = text "dynamic" <+> ppr conv
+ ppr (DNImport d) = ptext SLIT("dotnet") <+> ppr d
+ ppr (LblImport l) = ptext SLIT("label") <+> ppr l
+
+instance Outputable FoExport where
+ ppr (CExport d) = ppr d
+
+instance Outputable FoType where
+ ppr DNType = ptext SLIT("type dotnet")
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{Transformation rules}
+%* *
+%************************************************************************
+
+\begin{code}
+data RuleDecl name pat
+ = HsRule -- Source rule
+ FAST_STRING -- Rule name
+ [name] -- Forall'd tyvars, filled in by the renamer with
+ -- tyvars mentioned in sigs; then filled out by typechecker
+ [RuleBndr name] -- Forall'd term vars
+ (HsExpr name pat) -- LHS
+ (HsExpr name pat) -- RHS
+ SrcLoc
+
+ | IfaceRule -- One that's come in from an interface file; pre-typecheck
+ FAST_STRING
+ [UfBinder name] -- Tyvars and term vars
+ name -- Head of lhs
+ [UfExpr name] -- Args of LHS
+ (UfExpr name) -- Pre typecheck
+ SrcLoc
+
+ | IfaceRuleOut -- Post typecheck
+ name -- Head of LHS
+ CoreRule
+
+isIfaceRuleDecl (HsRule _ _ _ _ _ _) = False
+isIfaceRuleDecl other = True
+
+ifaceRuleDeclName :: RuleDecl name pat -> name
+ifaceRuleDeclName (IfaceRule _ _ n _ _ _) = n
+ifaceRuleDeclName (IfaceRuleOut n r) = n
+ifaceRuleDeclName (HsRule fs _ _ _ _ _) = pprPanic "ifaceRuleDeclName" (ppr fs)
+
+data RuleBndr name
+ = RuleBndr name
+ | RuleBndrSig name (HsType name)
+
+instance (NamedThing name, Ord name) => Eq (RuleDecl name pat) where
+ -- Works for IfaceRules only; used when comparing interface file versions
+ (IfaceRule n1 bs1 f1 es1 rhs1 _) == (IfaceRule n2 bs2 f2 es2 rhs2 _)
+ = n1==n2 && f1 == f2 &&
+ eq_ufBinders emptyEqHsEnv bs1 bs2 (\env ->
+ eqListBy (eq_ufExpr env) (rhs1:es1) (rhs2:es2))
+
+instance (NamedThing name, Outputable name, Outputable pat)
+ => Outputable (RuleDecl name pat) where
+ ppr (HsRule name tvs ns lhs rhs loc)
+ = sep [text "{-# RULES" <+> doubleQuotes (ptext name),
+ pp_forall, ppr lhs, equals <+> ppr rhs,
+ text "#-}" ]
+ where
+ pp_forall | null tvs && null ns = empty
+ | otherwise = text "forall" <+>
+ fsep (map ppr tvs ++ map ppr ns)
+ <> dot
+
+ ppr (IfaceRule name tpl_vars fn tpl_args rhs loc)
+ = hsep [ doubleQuotes (ptext name),
+ ptext SLIT("__forall") <+> braces (interppSP tpl_vars),
+ ppr fn <+> sep (map (pprUfExpr parens) tpl_args),
+ ptext SLIT("=") <+> ppr rhs
+ ] <+> semi
+
+ ppr (IfaceRuleOut fn rule) = pprCoreRule (ppr fn) rule
+
+instance Outputable 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}
+data DeprecDecl name = Deprecation name DeprecTxt SrcLoc
+
+type DeprecTxt = FAST_STRING -- reason/explanation for deprecation
+
+instance Outputable name => Outputable (DeprecDecl name) where
+ ppr (Deprecation thing txt _)
+ = hsep [text "{-# DEPRECATED", ppr thing, doubleQuotes (ppr txt), text "#-}"]
\end{code}