ghc-8.4.1: hsSyn/HsDecls.hs
{-
(c) The University of Glasgow 2006
(c) The GRASP/AQUA Project, Glasgow University, 1992-1998
-}
{-# LANGUAGE DeriveDataTypeable, DeriveFunctor, DeriveFoldable,
DeriveTraversable #-}
{-# LANGUAGE StandaloneDeriving #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE UndecidableInstances #-} -- Note [Pass sensitive types]
-- in module PlaceHolder
{-# LANGUAGE ConstraintKinds #-}
{-# LANGUAGE FlexibleInstances #-}
-- | Abstract syntax of global declarations.
--
-- Definitions for: @SynDecl@ and @ConDecl@, @ClassDecl@,
-- @InstDecl@, @DefaultDecl@ and @ForeignDecl@.
module HsDecls (
-- * Toplevel declarations
HsDecl(..), LHsDecl, HsDataDefn(..), HsDeriving,
HsDerivingClause(..), LHsDerivingClause,
-- ** Class or type declarations
TyClDecl(..), LTyClDecl,
TyClGroup(..), mkTyClGroup, emptyTyClGroup,
tyClGroupTyClDecls, tyClGroupInstDecls, tyClGroupRoleDecls,
isClassDecl, isDataDecl, isSynDecl, tcdName,
isFamilyDecl, isTypeFamilyDecl, isDataFamilyDecl,
isOpenTypeFamilyInfo, isClosedTypeFamilyInfo,
tyFamInstDeclName, tyFamInstDeclLName,
countTyClDecls, pprTyClDeclFlavour,
tyClDeclLName, tyClDeclTyVars,
hsDeclHasCusk, famDeclHasCusk,
FamilyDecl(..), LFamilyDecl,
-- ** Instance declarations
InstDecl(..), LInstDecl, NewOrData(..), FamilyInfo(..),
TyFamInstDecl(..), LTyFamInstDecl, instDeclDataFamInsts,
DataFamInstDecl(..), LDataFamInstDecl, pprDataFamInstFlavour, pprFamInstLHS,
FamInstEqn, LFamInstEqn, FamEqn(..),
TyFamInstEqn, LTyFamInstEqn, TyFamDefltEqn, LTyFamDefltEqn,
HsTyPats,
LClsInstDecl, ClsInstDecl(..),
-- ** Standalone deriving declarations
DerivDecl(..), LDerivDecl,
-- ** @RULE@ declarations
LRuleDecls,RuleDecls(..),RuleDecl(..), LRuleDecl, RuleBndr(..),LRuleBndr,
collectRuleBndrSigTys,
flattenRuleDecls, pprFullRuleName,
-- ** @VECTORISE@ declarations
VectDecl(..), LVectDecl,
lvectDeclName, lvectInstDecl,
-- ** @default@ declarations
DefaultDecl(..), LDefaultDecl,
-- ** Template haskell declaration splice
SpliceExplicitFlag(..),
SpliceDecl(..), LSpliceDecl,
-- ** Foreign function interface declarations
ForeignDecl(..), LForeignDecl, ForeignImport(..), ForeignExport(..),
noForeignImportCoercionYet, noForeignExportCoercionYet,
CImportSpec(..),
-- ** Data-constructor declarations
ConDecl(..), LConDecl,
HsConDeclDetails, hsConDeclArgTys,
getConNames,
getConDetails,
gadtDeclDetails,
-- ** Document comments
DocDecl(..), LDocDecl, docDeclDoc,
-- ** Deprecations
WarnDecl(..), LWarnDecl,
WarnDecls(..), LWarnDecls,
-- ** Annotations
AnnDecl(..), LAnnDecl,
AnnProvenance(..), annProvenanceName_maybe,
-- ** Role annotations
RoleAnnotDecl(..), LRoleAnnotDecl, roleAnnotDeclName,
-- ** Injective type families
FamilyResultSig(..), LFamilyResultSig, InjectivityAnn(..), LInjectivityAnn,
resultVariableName,
-- * Grouping
HsGroup(..), emptyRdrGroup, emptyRnGroup, appendGroups, hsGroupInstDecls
) where
-- friends:
import GhcPrelude
import {-# SOURCE #-} HsExpr( LHsExpr, HsExpr, HsSplice, pprExpr,
pprSpliceDecl )
-- Because Expr imports Decls via HsBracket
import HsBinds
import HsTypes
import HsDoc
import TyCon
import Name
import BasicTypes
import Coercion
import ForeignCall
import PlaceHolder ( PlaceHolder(..) )
import HsExtension
import NameSet
-- others:
import InstEnv
import Class
import Outputable
import Util
import SrcLoc
import Bag
import Maybes
import Data.Data hiding (TyCon,Fixity, Infix)
{-
************************************************************************
* *
\subsection[HsDecl]{Declarations}
* *
************************************************************************
-}
type LHsDecl id = Located (HsDecl id)
-- ^ When in a list this may have
--
-- - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnSemi'
--
-- For details on above see note [Api annotations] in ApiAnnotation
-- | A Haskell Declaration
data HsDecl id
= TyClD (TyClDecl id) -- ^ Type or Class Declaration
| InstD (InstDecl id) -- ^ Instance declaration
| DerivD (DerivDecl id) -- ^ Deriving declaration
| ValD (HsBind id) -- ^ Value declaration
| SigD (Sig id) -- ^ Signature declaration
| DefD (DefaultDecl id) -- ^ 'default' declaration
| ForD (ForeignDecl id) -- ^ Foreign declaration
| WarningD (WarnDecls id) -- ^ Warning declaration
| AnnD (AnnDecl id) -- ^ Annotation declaration
| RuleD (RuleDecls id) -- ^ Rule declaration
| VectD (VectDecl id) -- ^ Vectorise declaration
| SpliceD (SpliceDecl id) -- ^ Splice declaration
-- (Includes quasi-quotes)
| DocD (DocDecl) -- ^ Documentation comment declaration
| RoleAnnotD (RoleAnnotDecl id) -- ^ Role annotation declaration
deriving instance (DataId id) => Data (HsDecl 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
-- | Haskell Group
--
-- A 'HsDecl' is categorised into a 'HsGroup' before being
-- fed to the renamer.
data HsGroup id
= HsGroup {
hs_valds :: HsValBinds id,
hs_splcds :: [LSpliceDecl id],
hs_tyclds :: [TyClGroup id],
-- A list of mutually-recursive groups;
-- This includes `InstDecl`s as well;
-- Parser generates a singleton list;
-- renamer does dependency analysis
hs_derivds :: [LDerivDecl 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_warnds :: [LWarnDecls id],
hs_annds :: [LAnnDecl id],
hs_ruleds :: [LRuleDecls id],
hs_vects :: [LVectDecl id],
hs_docs :: [LDocDecl]
}
deriving instance (DataId id) => Data (HsGroup id)
emptyGroup, emptyRdrGroup, emptyRnGroup :: HsGroup a
emptyRdrGroup = emptyGroup { hs_valds = emptyValBindsIn }
emptyRnGroup = emptyGroup { hs_valds = emptyValBindsOut }
hsGroupInstDecls :: HsGroup id -> [LInstDecl id]
hsGroupInstDecls = (=<<) group_instds . hs_tyclds
emptyGroup = HsGroup { hs_tyclds = [],
hs_derivds = [],
hs_fixds = [], hs_defds = [], hs_annds = [],
hs_fords = [], hs_warnds = [], hs_ruleds = [], hs_vects = [],
hs_valds = error "emptyGroup hs_valds: Can't happen",
hs_splcds = [],
hs_docs = [] }
appendGroups :: HsGroup a -> HsGroup a -> HsGroup a
appendGroups
HsGroup {
hs_valds = val_groups1,
hs_splcds = spliceds1,
hs_tyclds = tyclds1,
hs_derivds = derivds1,
hs_fixds = fixds1,
hs_defds = defds1,
hs_annds = annds1,
hs_fords = fords1,
hs_warnds = warnds1,
hs_ruleds = rulds1,
hs_vects = vects1,
hs_docs = docs1 }
HsGroup {
hs_valds = val_groups2,
hs_splcds = spliceds2,
hs_tyclds = tyclds2,
hs_derivds = derivds2,
hs_fixds = fixds2,
hs_defds = defds2,
hs_annds = annds2,
hs_fords = fords2,
hs_warnds = warnds2,
hs_ruleds = rulds2,
hs_vects = vects2,
hs_docs = docs2 }
=
HsGroup {
hs_valds = val_groups1 `plusHsValBinds` val_groups2,
hs_splcds = spliceds1 ++ spliceds2,
hs_tyclds = tyclds1 ++ tyclds2,
hs_derivds = derivds1 ++ derivds2,
hs_fixds = fixds1 ++ fixds2,
hs_annds = annds1 ++ annds2,
hs_defds = defds1 ++ defds2,
hs_fords = fords1 ++ fords2,
hs_warnds = warnds1 ++ warnds2,
hs_ruleds = rulds1 ++ rulds2,
hs_vects = vects1 ++ vects2,
hs_docs = docs1 ++ docs2 }
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (HsDecl pass) where
ppr (TyClD dcl) = ppr dcl
ppr (ValD binds) = ppr binds
ppr (DefD def) = ppr def
ppr (InstD inst) = ppr inst
ppr (DerivD deriv) = ppr deriv
ppr (ForD fd) = ppr fd
ppr (SigD sd) = ppr sd
ppr (RuleD rd) = ppr rd
ppr (VectD vect) = ppr vect
ppr (WarningD wd) = ppr wd
ppr (AnnD ad) = ppr ad
ppr (SpliceD dd) = ppr dd
ppr (DocD doc) = ppr doc
ppr (RoleAnnotD ra) = ppr ra
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (HsGroup pass) where
ppr (HsGroup { hs_valds = val_decls,
hs_tyclds = tycl_decls,
hs_derivds = deriv_decls,
hs_fixds = fix_decls,
hs_warnds = deprec_decls,
hs_annds = ann_decls,
hs_fords = foreign_decls,
hs_defds = default_decls,
hs_ruleds = rule_decls,
hs_vects = vect_decls })
= vcat_mb empty
[ppr_ds fix_decls, ppr_ds default_decls,
ppr_ds deprec_decls, ppr_ds ann_decls,
ppr_ds rule_decls,
ppr_ds vect_decls,
if isEmptyValBinds val_decls
then Nothing
else Just (ppr val_decls),
ppr_ds (tyClGroupTyClDecls tycl_decls),
ppr_ds (tyClGroupInstDecls tycl_decls),
ppr_ds deriv_decls,
ppr_ds foreign_decls]
where
ppr_ds :: Outputable a => [a] -> Maybe SDoc
ppr_ds [] = Nothing
ppr_ds ds = Just (vcat (map ppr ds))
vcat_mb :: SDoc -> [Maybe SDoc] -> SDoc
-- Concatenate vertically with white-space between non-blanks
vcat_mb _ [] = empty
vcat_mb gap (Nothing : ds) = vcat_mb gap ds
vcat_mb gap (Just d : ds) = gap $$ d $$ vcat_mb blankLine ds
-- | Located Splice Declaration
type LSpliceDecl pass = Located (SpliceDecl pass)
-- | Splice Declaration
data SpliceDecl id
= SpliceDecl -- Top level splice
(Located (HsSplice id))
SpliceExplicitFlag
deriving instance (DataId id) => Data (SpliceDecl id)
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (SpliceDecl pass) where
ppr (SpliceDecl (L _ e) f) = pprSpliceDecl e f
{-
************************************************************************
* *
Type and class declarations
* *
************************************************************************
Note [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 DefMethInfo field.
(DefMethInfo is defined in Class.hs)
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 $dmop2.
The Class for Foo has a Nothing for op2 and
a Just ($dm_op1, VanillaDM) 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
-}
-- | Located Declaration of a Type or Class
type LTyClDecl pass = Located (TyClDecl pass)
-- | A type or class declaration.
data TyClDecl pass
= -- | @type/data family T :: *->*@
--
-- - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnType',
-- 'ApiAnnotation.AnnData',
-- 'ApiAnnotation.AnnFamily','ApiAnnotation.AnnDcolon',
-- 'ApiAnnotation.AnnWhere','ApiAnnotation.AnnOpenP',
-- 'ApiAnnotation.AnnDcolon','ApiAnnotation.AnnCloseP',
-- 'ApiAnnotation.AnnEqual','ApiAnnotation.AnnRarrow',
-- 'ApiAnnotation.AnnVbar'
-- For details on above see note [Api annotations] in ApiAnnotation
FamDecl { tcdFam :: FamilyDecl pass }
| -- | @type@ declaration
--
-- - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnType',
-- 'ApiAnnotation.AnnEqual',
-- For details on above see note [Api annotations] in ApiAnnotation
SynDecl { tcdLName :: Located (IdP pass) -- ^ Type constructor
, tcdTyVars :: LHsQTyVars pass -- ^ Type variables; for an
-- associated type these
-- include outer binders
, tcdFixity :: LexicalFixity -- ^ Fixity used in the declaration
, tcdRhs :: LHsType pass -- ^ RHS of type declaration
, tcdFVs :: PostRn pass NameSet }
| -- | @data@ declaration
--
-- - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnData',
-- 'ApiAnnotation.AnnFamily',
-- 'ApiAnnotation.AnnNewType',
-- 'ApiAnnotation.AnnNewType','ApiAnnotation.AnnDcolon'
-- 'ApiAnnotation.AnnWhere',
-- For details on above see note [Api annotations] in ApiAnnotation
DataDecl { tcdLName :: Located (IdP pass) -- ^ Type constructor
, tcdTyVars :: LHsQTyVars pass -- ^ Type variables; for an
-- associated type
-- these include outer binders
-- Eg class T a where
-- type F a :: *
-- type F a = a -> a
-- Here the type decl for 'f'
-- includes 'a' in its tcdTyVars
, tcdFixity :: LexicalFixity -- ^ Fixity used in the declaration
, tcdDataDefn :: HsDataDefn pass
, tcdDataCusk :: PostRn pass Bool -- ^ does this have a CUSK?
, tcdFVs :: PostRn pass NameSet }
| ClassDecl { tcdCtxt :: LHsContext pass, -- ^ Context...
tcdLName :: Located (IdP pass), -- ^ Name of the class
tcdTyVars :: LHsQTyVars pass, -- ^ Class type variables
tcdFixity :: LexicalFixity, -- ^ Fixity used in the declaration
tcdFDs :: [Located (FunDep (Located (IdP pass)))],
-- ^ Functional deps
tcdSigs :: [LSig pass], -- ^ Methods' signatures
tcdMeths :: LHsBinds pass, -- ^ Default methods
tcdATs :: [LFamilyDecl pass], -- ^ Associated types;
tcdATDefs :: [LTyFamDefltEqn pass],
-- ^ Associated type defaults
tcdDocs :: [LDocDecl], -- ^ Haddock docs
tcdFVs :: PostRn pass NameSet
}
-- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnClass',
-- 'ApiAnnotation.AnnWhere','ApiAnnotation.AnnOpen',
-- 'ApiAnnotation.AnnClose'
-- - The tcdFDs will have 'ApiAnnotation.AnnVbar',
-- 'ApiAnnotation.AnnComma'
-- 'ApiAnnotation.AnnRarrow'
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance (DataId id) => Data (TyClDecl id)
-- Simple classifiers for TyClDecl
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- | @True@ <=> argument is a @data@\/@newtype@
-- declaration.
isDataDecl :: TyClDecl pass -> Bool
isDataDecl (DataDecl {}) = True
isDataDecl _other = False
-- | type or type instance declaration
isSynDecl :: TyClDecl pass -> Bool
isSynDecl (SynDecl {}) = True
isSynDecl _other = False
-- | type class
isClassDecl :: TyClDecl pass -> Bool
isClassDecl (ClassDecl {}) = True
isClassDecl _ = False
-- | type/data family declaration
isFamilyDecl :: TyClDecl pass -> Bool
isFamilyDecl (FamDecl {}) = True
isFamilyDecl _other = False
-- | type family declaration
isTypeFamilyDecl :: TyClDecl pass -> Bool
isTypeFamilyDecl (FamDecl (FamilyDecl { fdInfo = info })) = case info of
OpenTypeFamily -> True
ClosedTypeFamily {} -> True
_ -> False
isTypeFamilyDecl _ = False
-- | open type family info
isOpenTypeFamilyInfo :: FamilyInfo pass -> Bool
isOpenTypeFamilyInfo OpenTypeFamily = True
isOpenTypeFamilyInfo _ = False
-- | closed type family info
isClosedTypeFamilyInfo :: FamilyInfo pass -> Bool
isClosedTypeFamilyInfo (ClosedTypeFamily {}) = True
isClosedTypeFamilyInfo _ = False
-- | data family declaration
isDataFamilyDecl :: TyClDecl pass -> Bool
isDataFamilyDecl (FamDecl (FamilyDecl { fdInfo = DataFamily })) = True
isDataFamilyDecl _other = False
-- Dealing with names
tyFamInstDeclName :: TyFamInstDecl pass -> (IdP pass)
tyFamInstDeclName = unLoc . tyFamInstDeclLName
tyFamInstDeclLName :: TyFamInstDecl pass -> Located (IdP pass)
tyFamInstDeclLName (TyFamInstDecl { tfid_eqn =
(HsIB { hsib_body = FamEqn { feqn_tycon = ln }}) })
= ln
tyClDeclLName :: TyClDecl pass -> Located (IdP pass)
tyClDeclLName (FamDecl { tcdFam = FamilyDecl { fdLName = ln } }) = ln
tyClDeclLName decl = tcdLName decl
tcdName :: TyClDecl pass -> (IdP pass)
tcdName = unLoc . tyClDeclLName
tyClDeclTyVars :: TyClDecl pass -> LHsQTyVars pass
tyClDeclTyVars (FamDecl { tcdFam = FamilyDecl { fdTyVars = tvs } }) = tvs
tyClDeclTyVars d = tcdTyVars d
countTyClDecls :: [TyClDecl pass] -> (Int, Int, Int, Int, Int)
-- class, synonym decls, data, newtype, family decls
countTyClDecls decls
= (count isClassDecl decls,
count isSynDecl decls, -- excluding...
count isDataTy decls, -- ...family...
count isNewTy decls, -- ...instances
count isFamilyDecl decls)
where
isDataTy DataDecl{ tcdDataDefn = HsDataDefn { dd_ND = DataType } } = True
isDataTy _ = False
isNewTy DataDecl{ tcdDataDefn = HsDataDefn { dd_ND = NewType } } = True
isNewTy _ = False
-- | Does this declaration have a complete, user-supplied kind signature?
-- See Note [Complete user-supplied kind signatures]
hsDeclHasCusk :: TyClDecl GhcRn -> Bool
hsDeclHasCusk (FamDecl { tcdFam = fam_decl }) = famDeclHasCusk Nothing fam_decl
hsDeclHasCusk (SynDecl { tcdTyVars = tyvars, tcdRhs = rhs })
-- NB: Keep this synchronized with 'getInitialKind'
= hsTvbAllKinded tyvars && rhs_annotated rhs
where
rhs_annotated (L _ ty) = case ty of
HsParTy lty -> rhs_annotated lty
HsKindSig {} -> True
_ -> False
hsDeclHasCusk (DataDecl { tcdDataCusk = cusk }) = cusk
hsDeclHasCusk (ClassDecl { tcdTyVars = tyvars }) = hsTvbAllKinded tyvars
-- Pretty-printing TyClDecl
-- ~~~~~~~~~~~~~~~~~~~~~~~~
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (TyClDecl pass) where
ppr (FamDecl { tcdFam = decl }) = ppr decl
ppr (SynDecl { tcdLName = ltycon, tcdTyVars = tyvars, tcdFixity = fixity
, tcdRhs = rhs })
= hang (text "type" <+>
pp_vanilla_decl_head ltycon tyvars fixity [] <+> equals)
4 (ppr rhs)
ppr (DataDecl { tcdLName = ltycon, tcdTyVars = tyvars, tcdFixity = fixity
, tcdDataDefn = defn })
= pp_data_defn (pp_vanilla_decl_head ltycon tyvars fixity) defn
ppr (ClassDecl {tcdCtxt = context, tcdLName = lclas, tcdTyVars = tyvars,
tcdFixity = fixity,
tcdFDs = fds,
tcdSigs = sigs, tcdMeths = methods,
tcdATs = ats, tcdATDefs = at_defs})
| null sigs && isEmptyBag methods && null ats && null at_defs -- No "where" part
= top_matter
| otherwise -- Laid out
= vcat [ top_matter <+> text "where"
, nest 2 $ pprDeclList (map (pprFamilyDecl NotTopLevel . unLoc) ats ++
map ppr_fam_deflt_eqn at_defs ++
pprLHsBindsForUser methods sigs) ]
where
top_matter = text "class"
<+> pp_vanilla_decl_head lclas tyvars fixity (unLoc context)
<+> pprFundeps (map unLoc fds)
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (TyClGroup pass) where
ppr (TyClGroup { group_tyclds = tyclds
, group_roles = roles
, group_instds = instds
}
)
= ppr tyclds $$
ppr roles $$
ppr instds
pp_vanilla_decl_head :: (SourceTextX pass, OutputableBndrId pass)
=> Located (IdP pass)
-> LHsQTyVars pass
-> LexicalFixity
-> HsContext pass
-> SDoc
pp_vanilla_decl_head thing (HsQTvs { hsq_explicit = tyvars }) fixity context
= hsep [pprHsContext context, pp_tyvars tyvars]
where
pp_tyvars (varl:varsr)
| fixity == Infix && length varsr > 1
= hsep [char '(',ppr (unLoc varl), pprInfixOcc (unLoc thing)
, (ppr.unLoc) (head varsr), char ')'
, hsep (map (ppr.unLoc) (tail varsr))]
| fixity == Infix
= hsep [ppr (unLoc varl), pprInfixOcc (unLoc thing)
, hsep (map (ppr.unLoc) varsr)]
| otherwise = hsep [ pprPrefixOcc (unLoc thing)
, hsep (map (ppr.unLoc) (varl:varsr))]
pp_tyvars [] = ppr thing
pprTyClDeclFlavour :: TyClDecl a -> SDoc
pprTyClDeclFlavour (ClassDecl {}) = text "class"
pprTyClDeclFlavour (SynDecl {}) = text "type"
pprTyClDeclFlavour (FamDecl { tcdFam = FamilyDecl { fdInfo = info }})
= pprFlavour info <+> text "family"
pprTyClDeclFlavour (DataDecl { tcdDataDefn = HsDataDefn { dd_ND = nd } })
= ppr nd
{- Note [Complete user-supplied kind signatures]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
We kind-check declarations differently if they have a complete, user-supplied
kind signature (CUSK). This is because we can safely generalise a CUSKed
declaration before checking all of the others, supporting polymorphic recursion.
See ghc.haskell.org/trac/ghc/wiki/GhcKinds/KindInference#Proposednewstrategy
and #9200 for lots of discussion of how we got here.
A declaration has a CUSK if we can know its complete kind without doing any
inference, at all. Here are the rules:
- A class or datatype is said to have a CUSK if and only if all of its type
variables are annotated. Its result kind is, by construction, Constraint or *
respectively.
- A type synonym has a CUSK if and only if all of its type variables and its
RHS are annotated with kinds.
- A closed type family is said to have a CUSK if and only if all of its type
variables and its return type are annotated.
- An open type family always has a CUSK -- unannotated type variables (and
return type) default to *.
- Additionally, if -XTypeInType is on, then a data definition with a top-level
:: must explicitly bind all kind variables to the right of the ::.
See test dependent/should_compile/KindLevels, which requires this case.
(Naturally, any kind variable mentioned before the :: should not be bound
after it.)
-}
{- *********************************************************************
* *
TyClGroup
Strongly connected components of
type, class, instance, and role declarations
* *
********************************************************************* -}
{- Note [TyClGroups and dependency analysis]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A TyClGroup represents a strongly connected components of type/class/instance
decls, together with the role annotations for the type/class declarations.
The hs_tyclds :: [TyClGroup] field of a HsGroup is a dependency-order
sequence of strongly-connected components.
Invariants
* The type and class declarations, group_tyclds, may depend on each
other, or earlier TyClGroups, but not on later ones
* The role annotations, group_roles, are role-annotations for some or
all of the types and classes in group_tyclds (only).
* The instance declarations, group_instds, may (and usually will)
depend on group_tyclds, or on earlier TyClGroups, but not on later
ones.
See Note [Dependency analsis of type, class, and instance decls]
in RnSource for more info.
-}
-- | Type or Class Group
data TyClGroup pass -- See Note [TyClGroups and dependency analysis]
= TyClGroup { group_tyclds :: [LTyClDecl pass]
, group_roles :: [LRoleAnnotDecl pass]
, group_instds :: [LInstDecl pass] }
deriving instance (DataId id) => Data (TyClGroup id)
emptyTyClGroup :: TyClGroup pass
emptyTyClGroup = TyClGroup [] [] []
tyClGroupTyClDecls :: [TyClGroup pass] -> [LTyClDecl pass]
tyClGroupTyClDecls = concatMap group_tyclds
tyClGroupInstDecls :: [TyClGroup pass] -> [LInstDecl pass]
tyClGroupInstDecls = concatMap group_instds
tyClGroupRoleDecls :: [TyClGroup pass] -> [LRoleAnnotDecl pass]
tyClGroupRoleDecls = concatMap group_roles
mkTyClGroup :: [LTyClDecl pass] -> [LInstDecl pass] -> TyClGroup pass
mkTyClGroup decls instds = TyClGroup
{ group_tyclds = decls
, group_roles = []
, group_instds = instds
}
{- *********************************************************************
* *
Data and type family declarations
* *
********************************************************************* -}
{- Note [FamilyResultSig]
~~~~~~~~~~~~~~~~~~~~~~~~~
This data type represents the return signature of a type family. Possible
values are:
* NoSig - the user supplied no return signature:
type family Id a where ...
* KindSig - the user supplied the return kind:
type family Id a :: * where ...
* TyVarSig - user named the result with a type variable and possibly
provided a kind signature for that variable:
type family Id a = r where ...
type family Id a = (r :: *) where ...
Naming result of a type family is required if we want to provide
injectivity annotation for a type family:
type family Id a = r | r -> a where ...
See also: Note [Injectivity annotation]
Note [Injectivity annotation]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A user can declare a type family to be injective:
type family Id a = r | r -> a where ...
* The part after the "|" is called "injectivity annotation".
* "r -> a" part is called "injectivity condition"; at the moment terms
"injectivity annotation" and "injectivity condition" are synonymous
because we only allow a single injectivity condition.
* "r" is the "LHS of injectivity condition". LHS can only contain the
variable naming the result of a type family.
* "a" is the "RHS of injectivity condition". RHS contains space-separated
type and kind variables representing the arguments of a type
family. Variables can be omitted if a type family is not injective in
these arguments. Example:
type family Foo a b c = d | d -> a c where ...
Note that:
(a) naming of type family result is required to provide injectivity
annotation
(b) for associated types if the result was named then injectivity annotation
is mandatory. Otherwise result type variable is indistinguishable from
associated type default.
It is possible that in the future this syntax will be extended to support
more complicated injectivity annotations. For example we could declare that
if we know the result of Plus and one of its arguments we can determine the
other argument:
type family Plus a b = (r :: Nat) | r a -> b, r b -> a where ...
Here injectivity annotation would consist of two comma-separated injectivity
conditions.
See also Note [Injective type families] in TyCon
-}
-- | Located type Family Result Signature
type LFamilyResultSig pass = Located (FamilyResultSig pass)
-- | type Family Result Signature
data FamilyResultSig pass = -- see Note [FamilyResultSig]
NoSig
-- ^ - 'ApiAnnotation.AnnKeywordId' :
-- For details on above see note [Api annotations] in ApiAnnotation
| KindSig (LHsKind pass)
-- ^ - 'ApiAnnotation.AnnKeywordId' :
-- 'ApiAnnotation.AnnOpenP','ApiAnnotation.AnnDcolon',
-- 'ApiAnnotation.AnnCloseP'
-- For details on above see note [Api annotations] in ApiAnnotation
| TyVarSig (LHsTyVarBndr pass)
-- ^ - 'ApiAnnotation.AnnKeywordId' :
-- 'ApiAnnotation.AnnOpenP','ApiAnnotation.AnnDcolon',
-- 'ApiAnnotation.AnnCloseP', 'ApiAnnotation.AnnEqual'
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance (DataId pass) => Data (FamilyResultSig pass)
-- | Located type Family Declaration
type LFamilyDecl pass = Located (FamilyDecl pass)
-- | type Family Declaration
data FamilyDecl pass = FamilyDecl
{ fdInfo :: FamilyInfo pass -- type/data, closed/open
, fdLName :: Located (IdP pass) -- type constructor
, fdTyVars :: LHsQTyVars pass -- type variables
, fdFixity :: LexicalFixity -- Fixity used in the declaration
, fdResultSig :: LFamilyResultSig pass -- result signature
, fdInjectivityAnn :: Maybe (LInjectivityAnn pass) -- optional injectivity ann
}
-- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnType',
-- 'ApiAnnotation.AnnData', 'ApiAnnotation.AnnFamily',
-- 'ApiAnnotation.AnnWhere', 'ApiAnnotation.AnnOpenP',
-- 'ApiAnnotation.AnnDcolon', 'ApiAnnotation.AnnCloseP',
-- 'ApiAnnotation.AnnEqual', 'ApiAnnotation.AnnRarrow',
-- 'ApiAnnotation.AnnVbar'
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance (DataId id) => Data (FamilyDecl id)
-- | Located Injectivity Annotation
type LInjectivityAnn pass = Located (InjectivityAnn pass)
-- | If the user supplied an injectivity annotation it is represented using
-- InjectivityAnn. At the moment this is a single injectivity condition - see
-- Note [Injectivity annotation]. `Located name` stores the LHS of injectivity
-- condition. `[Located name]` stores the RHS of injectivity condition. Example:
--
-- type family Foo a b c = r | r -> a c where ...
--
-- This will be represented as "InjectivityAnn `r` [`a`, `c`]"
data InjectivityAnn pass
= InjectivityAnn (Located (IdP pass)) [Located (IdP pass)]
-- ^ - 'ApiAnnotation.AnnKeywordId' :
-- 'ApiAnnotation.AnnRarrow', 'ApiAnnotation.AnnVbar'
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance (DataId pass) => Data (InjectivityAnn pass)
data FamilyInfo pass
= DataFamily
| OpenTypeFamily
-- | 'Nothing' if we're in an hs-boot file and the user
-- said "type family Foo x where .."
| ClosedTypeFamily (Maybe [LTyFamInstEqn pass])
deriving instance (DataId pass) => Data (FamilyInfo pass)
-- | Does this family declaration have a complete, user-supplied kind signature?
famDeclHasCusk :: Maybe Bool
-- ^ if associated, does the enclosing class have a CUSK?
-> FamilyDecl pass -> Bool
famDeclHasCusk _ (FamilyDecl { fdInfo = ClosedTypeFamily _
, fdTyVars = tyvars
, fdResultSig = L _ resultSig })
= hsTvbAllKinded tyvars && hasReturnKindSignature resultSig
famDeclHasCusk mb_class_cusk _ = mb_class_cusk `orElse` True
-- all un-associated open families have CUSKs!
-- | Does this family declaration have user-supplied return kind signature?
hasReturnKindSignature :: FamilyResultSig a -> Bool
hasReturnKindSignature NoSig = False
hasReturnKindSignature (TyVarSig (L _ (UserTyVar _))) = False
hasReturnKindSignature _ = True
-- | Maybe return name of the result type variable
resultVariableName :: FamilyResultSig a -> Maybe (IdP a)
resultVariableName (TyVarSig sig) = Just $ hsLTyVarName sig
resultVariableName _ = Nothing
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (FamilyDecl pass) where
ppr = pprFamilyDecl TopLevel
pprFamilyDecl :: (SourceTextX pass, OutputableBndrId pass)
=> TopLevelFlag -> FamilyDecl pass -> SDoc
pprFamilyDecl top_level (FamilyDecl { fdInfo = info, fdLName = ltycon
, fdTyVars = tyvars
, fdFixity = fixity
, fdResultSig = L _ result
, fdInjectivityAnn = mb_inj })
= vcat [ pprFlavour info <+> pp_top_level <+>
pp_vanilla_decl_head ltycon tyvars fixity [] <+>
pp_kind <+> pp_inj <+> pp_where
, nest 2 $ pp_eqns ]
where
pp_top_level = case top_level of
TopLevel -> text "family"
NotTopLevel -> empty
pp_kind = case result of
NoSig -> empty
KindSig kind -> dcolon <+> ppr kind
TyVarSig tv_bndr -> text "=" <+> ppr tv_bndr
pp_inj = case mb_inj of
Just (L _ (InjectivityAnn lhs rhs)) ->
hsep [ vbar, ppr lhs, text "->", hsep (map ppr rhs) ]
Nothing -> empty
(pp_where, pp_eqns) = case info of
ClosedTypeFamily mb_eqns ->
( text "where"
, case mb_eqns of
Nothing -> text ".."
Just eqns -> vcat $ map (ppr_fam_inst_eqn . unLoc) eqns )
_ -> (empty, empty)
pprFlavour :: FamilyInfo pass -> SDoc
pprFlavour DataFamily = text "data"
pprFlavour OpenTypeFamily = text "type"
pprFlavour (ClosedTypeFamily {}) = text "type"
instance Outputable (FamilyInfo pass) where
ppr info = pprFlavour info <+> text "family"
{- *********************************************************************
* *
Data types and data constructors
* *
********************************************************************* -}
-- | Haskell Data type Definition
data HsDataDefn pass -- The payload of a data type defn
-- Used *both* for vanilla data declarations,
-- *and* for data family instances
= -- | Declares a data type or newtype, giving its constructors
-- @
-- data/newtype T a = <constrs>
-- data/newtype instance T [a] = <constrs>
-- @
HsDataDefn { dd_ND :: NewOrData,
dd_ctxt :: LHsContext pass, -- ^ Context
dd_cType :: Maybe (Located CType),
dd_kindSig:: Maybe (LHsKind pass),
-- ^ Optional kind signature.
--
-- @(Just k)@ for a GADT-style @data@,
-- or @data instance@ decl, with explicit kind sig
--
-- Always @Nothing@ for H98-syntax decls
dd_cons :: [LConDecl pass],
-- ^ Data constructors
--
-- For @data T a = T1 | T2 a@
-- the 'LConDecl's all have 'ConDeclH98'.
-- For @data T a where { T1 :: T a }@
-- the 'LConDecls' all have 'ConDeclGADT'.
dd_derivs :: HsDeriving pass -- ^ Optional 'deriving' claues
-- For details on above see note [Api annotations] in ApiAnnotation
}
deriving instance (DataId id) => Data (HsDataDefn id)
-- | Haskell Deriving clause
type HsDeriving pass = Located [LHsDerivingClause pass]
-- ^ The optional @deriving@ clauses of a data declaration. "Clauses" is
-- plural because one can specify multiple deriving clauses using the
-- @-XDerivingStrategies@ language extension.
--
-- The list of 'LHsDerivingClause's corresponds to exactly what the user
-- requested to derive, in order. If no deriving clauses were specified,
-- the list is empty.
type LHsDerivingClause pass = Located (HsDerivingClause pass)
-- | A single @deriving@ clause of a data declaration.
--
-- - 'ApiAnnotation.AnnKeywordId' :
-- 'ApiAnnotation.AnnDeriving', 'ApiAnnotation.AnnStock',
-- 'ApiAnnotation.AnnAnyClass', 'Api.AnnNewtype',
-- 'ApiAnnotation.AnnOpen','ApiAnnotation.AnnClose'
data HsDerivingClause pass
-- See Note [Deriving strategies] in TcDeriv
= HsDerivingClause
{ deriv_clause_strategy :: Maybe (Located DerivStrategy)
-- ^ The user-specified strategy (if any) to use when deriving
-- 'deriv_clause_tys'.
, deriv_clause_tys :: Located [LHsSigType pass]
-- ^ The types to derive.
--
-- It uses 'LHsSigType's because, with @-XGeneralizedNewtypeDeriving@,
-- we can mention type variables that aren't bound by the datatype, e.g.
--
-- > data T b = ... deriving (C [a])
--
-- should produce a derived instance for @C [a] (T b)@.
}
deriving instance (DataId id) => Data (HsDerivingClause id)
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (HsDerivingClause pass) where
ppr (HsDerivingClause { deriv_clause_strategy = dcs
, deriv_clause_tys = L _ dct })
= hsep [ text "deriving"
, ppDerivStrategy dcs
, pp_dct dct ]
where
-- This complexity is to distinguish between
-- deriving Show
-- deriving (Show)
pp_dct [a@(HsIB { hsib_body = ty })]
| isCompoundHsType ty = parens (ppr a)
| otherwise = ppr a
pp_dct _ = parens (interpp'SP dct)
data NewOrData
= NewType -- ^ @newtype Blah ...@
| DataType -- ^ @data Blah ...@
deriving( Eq, Data ) -- Needed because Demand derives Eq
-- | Located data Constructor Declaration
type LConDecl pass = Located (ConDecl pass)
-- ^ May have 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnSemi' when
-- in a GADT constructor list
-- For details on above see note [Api annotations] in ApiAnnotation
-- |
--
-- @
-- data T b = forall a. Eq a => MkT a b
-- MkT :: forall b a. Eq a => MkT a b
--
-- data T b where
-- MkT1 :: Int -> T Int
--
-- data T = Int `MkT` Int
-- | MkT2
--
-- data T a where
-- Int `MkT` Int :: T Int
-- @
--
-- - 'ApiAnnotation.AnnKeywordId's : 'ApiAnnotation.AnnOpen',
-- 'ApiAnnotation.AnnDotdot','ApiAnnotation.AnnCLose',
-- 'ApiAnnotation.AnnEqual','ApiAnnotation.AnnVbar',
-- 'ApiAnnotation.AnnDarrow','ApiAnnotation.AnnDarrow',
-- 'ApiAnnotation.AnnForall','ApiAnnotation.AnnDot'
-- For details on above see note [Api annotations] in ApiAnnotation
-- | data Constructor Declaration
data ConDecl pass
= ConDeclGADT
{ con_names :: [Located (IdP pass)]
, con_type :: LHsSigType pass
-- ^ The type after the ‘::’
, con_doc :: Maybe LHsDocString
-- ^ A possible Haddock comment.
}
| ConDeclH98
{ con_name :: Located (IdP pass)
, con_qvars :: Maybe (LHsQTyVars pass)
-- User-written forall (if any), and its implicit
-- kind variables
-- Non-Nothing means an explicit user-written forall
-- e.g. data T a = forall b. MkT b (b->a)
-- con_qvars = {b}
, con_cxt :: Maybe (LHsContext pass)
-- ^ User-written context (if any)
, con_details :: HsConDeclDetails pass
-- ^ Arguments
, con_doc :: Maybe LHsDocString
-- ^ A possible Haddock comment.
}
deriving instance (DataId pass) => Data (ConDecl pass)
-- | Haskell data Constructor Declaration Details
type HsConDeclDetails pass
= HsConDetails (LBangType pass) (Located [LConDeclField pass])
getConNames :: ConDecl pass -> [Located (IdP pass)]
getConNames ConDeclH98 {con_name = name} = [name]
getConNames ConDeclGADT {con_names = names} = names
-- don't call with RdrNames, because it can't deal with HsAppsTy
getConDetails :: ConDecl pass -> HsConDeclDetails pass
getConDetails ConDeclH98 {con_details = details} = details
getConDetails ConDeclGADT {con_type = ty } = details
where
(details,_,_,_) = gadtDeclDetails ty
-- don't call with RdrNames, because it can't deal with HsAppsTy
gadtDeclDetails :: LHsSigType pass
-> ( HsConDeclDetails pass
, LHsType pass
, LHsContext pass
, [LHsTyVarBndr pass] )
gadtDeclDetails HsIB {hsib_body = lbody_ty} = (details,res_ty,cxt,tvs)
where
(tvs, cxt, tau) = splitLHsSigmaTy lbody_ty
(details, res_ty) -- See Note [Sorting out the result type]
= case tau of
L _ (HsFunTy (L l (HsRecTy flds)) res_ty')
-> (RecCon (L l flds), res_ty')
_other -> (PrefixCon [], tau)
hsConDeclArgTys :: HsConDeclDetails pass -> [LBangType pass]
hsConDeclArgTys (PrefixCon tys) = tys
hsConDeclArgTys (InfixCon ty1 ty2) = [ty1,ty2]
hsConDeclArgTys (RecCon flds) = map (cd_fld_type . unLoc) (unLoc flds)
pp_data_defn :: (SourceTextX pass, OutputableBndrId pass)
=> (HsContext pass -> SDoc) -- Printing the header
-> HsDataDefn pass
-> SDoc
pp_data_defn pp_hdr (HsDataDefn { dd_ND = new_or_data, dd_ctxt = L _ context
, dd_cType = mb_ct
, dd_kindSig = mb_sig
, dd_cons = condecls, dd_derivs = derivings })
| null condecls
= ppr new_or_data <+> pp_ct <+> pp_hdr context <+> pp_sig
<+> pp_derivings derivings
| otherwise
= hang (ppr new_or_data <+> pp_ct <+> pp_hdr context <+> pp_sig)
2 (pp_condecls condecls $$ pp_derivings derivings)
where
pp_ct = case mb_ct of
Nothing -> empty
Just ct -> ppr ct
pp_sig = case mb_sig of
Nothing -> empty
Just kind -> dcolon <+> ppr kind
pp_derivings (L _ ds) = vcat (map ppr ds)
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (HsDataDefn pass) where
ppr d = pp_data_defn (\_ -> text "Naked HsDataDefn") d
instance Outputable NewOrData where
ppr NewType = text "newtype"
ppr DataType = text "data"
pp_condecls :: (SourceTextX pass, OutputableBndrId pass)
=> [LConDecl pass] -> SDoc
pp_condecls cs@(L _ ConDeclGADT{} : _) -- In GADT syntax
= hang (text "where") 2 (vcat (map ppr cs))
pp_condecls cs -- In H98 syntax
= equals <+> sep (punctuate (text " |") (map ppr cs))
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (ConDecl pass) where
ppr = pprConDecl
pprConDecl :: (SourceTextX pass, OutputableBndrId pass) => ConDecl pass -> SDoc
pprConDecl (ConDeclH98 { con_name = L _ con
, con_qvars = mtvs
, con_cxt = mcxt
, con_details = details
, con_doc = doc })
= sep [ppr_mbDoc doc, pprHsForAll tvs cxt, ppr_details details]
where
ppr_details (InfixCon t1 t2) = hsep [ppr t1, pprInfixOcc con, ppr t2]
ppr_details (PrefixCon tys) = hsep (pprPrefixOcc con
: map (pprHsType . unLoc) tys)
ppr_details (RecCon fields) = pprPrefixOcc con
<+> pprConDeclFields (unLoc fields)
tvs = case mtvs of
Nothing -> []
Just (HsQTvs { hsq_explicit = tvs }) -> tvs
cxt = fromMaybe (noLoc []) mcxt
pprConDecl (ConDeclGADT { con_names = cons, con_type = res_ty, con_doc = doc })
= sep [ppr_mbDoc doc <+> ppr_con_names cons <+> dcolon
<+> ppr res_ty]
ppr_con_names :: (OutputableBndr a) => [Located a] -> SDoc
ppr_con_names = pprWithCommas (pprPrefixOcc . unLoc)
{-
************************************************************************
* *
Instance declarations
* *
************************************************************************
Note [Type family instance declarations in HsSyn]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The data type FamEqn represents one equation of a type family instance.
Aside from the pass, it is also parameterised over two fields:
feqn_pats and feqn_rhs.
feqn_pats is either LHsTypes (for ordinary data/type family instances) or
LHsQTyVars (for associated type family default instances). In particular:
* An ordinary type family instance declaration looks like this in source Haskell
type instance T [a] Int = a -> a
(or something similar for a closed family)
It is represented by a FamInstEqn, with a *type* (LHsType) in the feqn_pats
field.
* On the other hand, the *default instance* of an associated type looks like
this in source Haskell
class C a where
type T a b
type T a b = a -> b -- The default instance
It is represented by a TyFamDefltEqn, with *type variables* (LHsQTyVars) in
the feqn_pats field.
feqn_rhs is either an HsDataDefn (for data family instances) or an LHsType
(for type family instances).
-}
----------------- Type synonym family instances -------------
-- | Located Type Family Instance Equation
type LTyFamInstEqn pass = Located (TyFamInstEqn pass)
-- ^ May have 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnSemi'
-- when in a list
-- For details on above see note [Api annotations] in ApiAnnotation
-- | Located Type Family Default Equation
type LTyFamDefltEqn pass = Located (TyFamDefltEqn pass)
-- | Haskell Type Patterns
type HsTyPats pass = [LHsType pass]
{- Note [Family instance declaration binders]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
For ordinary data/type family instances, the feqn_pats field of FamEqn stores
the LHS type (and kind) patterns. These type patterns can of course contain
type (and kind) variables, which are bound in the hsib_vars field of the
HsImplicitBndrs in FamInstEqn. Note in particular
* The hsib_vars *includes* any anonymous wildcards. For example
type instance F a _ = a
The hsib_vars will be {a, _}. Remember that each separate wildcard
'_' gets its own unique. In this context wildcards behave just like
an ordinary type variable, only anonymous.
* The hsib_vars *includes* type variables that are already in scope
Eg class C s t where
type F t p :: *
instance C w (a,b) where
type F (a,b) x = x->a
The hsib_vars of the F decl are {a,b,x}, even though the F decl
is nested inside the 'instance' decl.
However after the renamer, the uniques will match up:
instance C w7 (a8,b9) where
type F (a8,b9) x10 = x10->a8
so that we can compare the type pattern in the 'instance' decl and
in the associated 'type' decl
For associated type family default instances (TyFamDefltEqn), instead of using
type patterns with binders in a surrounding HsImplicitBndrs, we use raw type
variables (LHsQTyVars) in the feqn_pats field of FamEqn.
-}
-- | Type Family Instance Equation
type TyFamInstEqn pass = FamInstEqn pass (LHsType pass)
-- | Type Family Default Equation
type TyFamDefltEqn pass = FamEqn pass (LHsQTyVars pass) (LHsType pass)
-- See Note [Type family instance declarations in HsSyn]
-- | Located Type Family Instance Declaration
type LTyFamInstDecl pass = Located (TyFamInstDecl pass)
-- | Type Family Instance Declaration
newtype TyFamInstDecl pass = TyFamInstDecl { tfid_eqn :: TyFamInstEqn pass }
-- ^
-- - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnType',
-- 'ApiAnnotation.AnnInstance',
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance DataId pass => Data (TyFamInstDecl pass)
----------------- Data family instances -------------
-- | Located Data Family Instance Declaration
type LDataFamInstDecl pass = Located (DataFamInstDecl pass)
-- | Data Family Instance Declaration
newtype DataFamInstDecl pass
= DataFamInstDecl { dfid_eqn :: FamInstEqn pass (HsDataDefn pass) }
-- ^
-- - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnData',
-- 'ApiAnnotation.AnnNewType','ApiAnnotation.AnnInstance',
-- 'ApiAnnotation.AnnDcolon'
-- 'ApiAnnotation.AnnWhere','ApiAnnotation.AnnOpen',
-- 'ApiAnnotation.AnnClose'
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance DataId pass => Data (DataFamInstDecl pass)
----------------- Family instances (common types) -------------
-- | Located Family Instance Equation
type LFamInstEqn pass rhs = Located (FamInstEqn pass rhs)
-- | Family Instance Equation
type FamInstEqn pass rhs
= HsImplicitBndrs pass (FamEqn pass (HsTyPats pass) rhs)
-- ^ Here, the @pats@ are type patterns (with kind and type bndrs).
-- See Note [Family instance declaration binders]
-- | Family Equation
--
-- One equation in a type family instance declaration, data family instance
-- declaration, or type family default.
-- See Note [Type family instance declarations in HsSyn]
-- See Note [Family instance declaration binders]
data FamEqn pass pats rhs
= FamEqn
{ feqn_tycon :: Located (IdP pass)
, feqn_pats :: pats
, feqn_fixity :: LexicalFixity -- ^ Fixity used in the declaration
, feqn_rhs :: rhs
}
-- ^
-- - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnEqual'
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance (DataId pass, Data pats, Data rhs)
=> Data (FamEqn pass pats rhs)
----------------- Class instances -------------
-- | Located Class Instance Declaration
type LClsInstDecl pass = Located (ClsInstDecl pass)
-- | Class Instance Declaration
data ClsInstDecl pass
= ClsInstDecl
{ cid_poly_ty :: LHsSigType pass -- Context => Class Instance-type
-- Using a polytype means that the renamer conveniently
-- figures out the quantified type variables for us.
, cid_binds :: LHsBinds pass -- Class methods
, cid_sigs :: [LSig pass] -- User-supplied pragmatic info
, cid_tyfam_insts :: [LTyFamInstDecl pass] -- Type family instances
, cid_datafam_insts :: [LDataFamInstDecl pass] -- Data family instances
, cid_overlap_mode :: Maybe (Located OverlapMode)
-- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
-- 'ApiAnnotation.AnnClose',
-- For details on above see note [Api annotations] in ApiAnnotation
}
-- ^
-- - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnInstance',
-- 'ApiAnnotation.AnnWhere',
-- 'ApiAnnotation.AnnOpen','ApiAnnotation.AnnClose',
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance (DataId id) => Data (ClsInstDecl id)
----------------- Instances of all kinds -------------
-- | Located Instance Declaration
type LInstDecl pass = Located (InstDecl pass)
-- | Instance Declaration
data InstDecl pass -- Both class and family instances
= ClsInstD
{ cid_inst :: ClsInstDecl pass }
| DataFamInstD -- data family instance
{ dfid_inst :: DataFamInstDecl pass }
| TyFamInstD -- type family instance
{ tfid_inst :: TyFamInstDecl pass }
deriving instance (DataId id) => Data (InstDecl id)
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (TyFamInstDecl pass) where
ppr = pprTyFamInstDecl TopLevel
pprTyFamInstDecl :: (SourceTextX pass, OutputableBndrId pass)
=> TopLevelFlag -> TyFamInstDecl pass -> SDoc
pprTyFamInstDecl top_lvl (TyFamInstDecl { tfid_eqn = eqn })
= text "type" <+> ppr_instance_keyword top_lvl <+> ppr_fam_inst_eqn eqn
ppr_instance_keyword :: TopLevelFlag -> SDoc
ppr_instance_keyword TopLevel = text "instance"
ppr_instance_keyword NotTopLevel = empty
ppr_fam_inst_eqn :: (SourceTextX pass, OutputableBndrId pass)
=> TyFamInstEqn pass -> SDoc
ppr_fam_inst_eqn (HsIB { hsib_body = FamEqn { feqn_tycon = tycon
, feqn_pats = pats
, feqn_fixity = fixity
, feqn_rhs = rhs }})
= pprFamInstLHS tycon pats fixity [] Nothing <+> equals <+> ppr rhs
ppr_fam_deflt_eqn :: (SourceTextX pass, OutputableBndrId pass)
=> LTyFamDefltEqn pass -> SDoc
ppr_fam_deflt_eqn (L _ (FamEqn { feqn_tycon = tycon
, feqn_pats = tvs
, feqn_fixity = fixity
, feqn_rhs = rhs }))
= text "type" <+> pp_vanilla_decl_head tycon tvs fixity []
<+> equals <+> ppr rhs
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (DataFamInstDecl pass) where
ppr = pprDataFamInstDecl TopLevel
pprDataFamInstDecl :: (SourceTextX pass, OutputableBndrId pass)
=> TopLevelFlag -> DataFamInstDecl pass -> SDoc
pprDataFamInstDecl top_lvl (DataFamInstDecl { dfid_eqn = HsIB { hsib_body =
FamEqn { feqn_tycon = tycon
, feqn_pats = pats
, feqn_fixity = fixity
, feqn_rhs = defn }}})
= pp_data_defn pp_hdr defn
where
pp_hdr ctxt = ppr_instance_keyword top_lvl
<+> pprFamInstLHS tycon pats fixity ctxt (dd_kindSig defn)
pprDataFamInstFlavour :: DataFamInstDecl pass -> SDoc
pprDataFamInstFlavour (DataFamInstDecl { dfid_eqn = HsIB { hsib_body =
FamEqn { feqn_rhs = HsDataDefn { dd_ND = nd }}}})
= ppr nd
pprFamInstLHS :: (SourceTextX pass, OutputableBndrId pass)
=> Located (IdP pass)
-> HsTyPats pass
-> LexicalFixity
-> HsContext pass
-> Maybe (LHsKind pass)
-> SDoc
pprFamInstLHS thing typats fixity context mb_kind_sig
-- explicit type patterns
= hsep [ pprHsContext context, pp_pats typats, pp_kind_sig ]
where
pp_pats (patl:patsr)
| fixity == Infix
= hsep [pprHsType (unLoc patl), pprInfixOcc (unLoc thing)
, hsep (map (pprHsType.unLoc) patsr)]
| otherwise = hsep [ pprPrefixOcc (unLoc thing)
, hsep (map (pprHsType.unLoc) (patl:patsr))]
pp_pats [] = pprPrefixOcc (unLoc thing)
pp_kind_sig
| Just k <- mb_kind_sig
= dcolon <+> ppr k
| otherwise
= empty
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (ClsInstDecl pass) where
ppr (ClsInstDecl { cid_poly_ty = inst_ty, cid_binds = binds
, cid_sigs = sigs, cid_tyfam_insts = ats
, cid_overlap_mode = mbOverlap
, cid_datafam_insts = adts })
| null sigs, null ats, null adts, isEmptyBag binds -- No "where" part
= top_matter
| otherwise -- Laid out
= vcat [ top_matter <+> text "where"
, nest 2 $ pprDeclList $
map (pprTyFamInstDecl NotTopLevel . unLoc) ats ++
map (pprDataFamInstDecl NotTopLevel . unLoc) adts ++
pprLHsBindsForUser binds sigs ]
where
top_matter = text "instance" <+> ppOverlapPragma mbOverlap
<+> ppr inst_ty
ppDerivStrategy :: Maybe (Located DerivStrategy) -> SDoc
ppDerivStrategy mb =
case mb of
Nothing -> empty
Just (L _ ds) -> ppr ds
ppOverlapPragma :: Maybe (Located OverlapMode) -> SDoc
ppOverlapPragma mb =
case mb of
Nothing -> empty
Just (L _ (NoOverlap s)) -> maybe_stext s "{-# NO_OVERLAP #-}"
Just (L _ (Overlappable s)) -> maybe_stext s "{-# OVERLAPPABLE #-}"
Just (L _ (Overlapping s)) -> maybe_stext s "{-# OVERLAPPING #-}"
Just (L _ (Overlaps s)) -> maybe_stext s "{-# OVERLAPS #-}"
Just (L _ (Incoherent s)) -> maybe_stext s "{-# INCOHERENT #-}"
where
maybe_stext NoSourceText alt = text alt
maybe_stext (SourceText src) _ = text src <+> text "#-}"
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (InstDecl pass) where
ppr (ClsInstD { cid_inst = decl }) = ppr decl
ppr (TyFamInstD { tfid_inst = decl }) = ppr decl
ppr (DataFamInstD { dfid_inst = decl }) = ppr decl
-- Extract the declarations of associated data types from an instance
instDeclDataFamInsts :: [LInstDecl pass] -> [DataFamInstDecl pass]
instDeclDataFamInsts inst_decls
= concatMap do_one inst_decls
where
do_one (L _ (ClsInstD { cid_inst = ClsInstDecl { cid_datafam_insts = fam_insts } }))
= map unLoc fam_insts
do_one (L _ (DataFamInstD { dfid_inst = fam_inst })) = [fam_inst]
do_one (L _ (TyFamInstD {})) = []
{-
************************************************************************
* *
\subsection[DerivDecl]{A stand-alone instance deriving declaration}
* *
************************************************************************
-}
-- | Located Deriving Declaration
type LDerivDecl pass = Located (DerivDecl pass)
-- | Deriving Declaration
data DerivDecl pass = DerivDecl
{ deriv_type :: LHsSigType pass
, deriv_strategy :: Maybe (Located DerivStrategy)
, deriv_overlap_mode :: Maybe (Located OverlapMode)
-- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnDeriving',
-- 'ApiAnnotation.AnnInstance', 'ApiAnnotation.AnnStock',
-- 'ApiAnnotation.AnnAnyClass', 'Api.AnnNewtype',
-- 'ApiAnnotation.AnnOpen','ApiAnnotation.AnnClose'
-- For details on above see note [Api annotations] in ApiAnnotation
}
deriving instance (DataId pass) => Data (DerivDecl pass)
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (DerivDecl pass) where
ppr (DerivDecl { deriv_type = ty
, deriv_strategy = ds
, deriv_overlap_mode = o })
= hsep [ text "deriving"
, ppDerivStrategy ds
, text "instance"
, ppOverlapPragma o
, ppr ty ]
{-
************************************************************************
* *
\subsection[DefaultDecl]{A @default@ declaration}
* *
************************************************************************
There can only be one default declaration per module, but it is hard
for the parser to check that; we pass them all through in the abstract
syntax, and that restriction must be checked in the front end.
-}
-- | Located Default Declaration
type LDefaultDecl pass = Located (DefaultDecl pass)
-- | Default Declaration
data DefaultDecl pass
= DefaultDecl [LHsType pass]
-- ^ - 'ApiAnnotation.AnnKeywordId's : 'ApiAnnotation.AnnDefault',
-- 'ApiAnnotation.AnnOpen','ApiAnnotation.AnnClose'
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance (DataId pass) => Data (DefaultDecl pass)
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (DefaultDecl pass) where
ppr (DefaultDecl tys)
= text "default" <+> parens (interpp'SP tys)
{-
************************************************************************
* *
\subsection{Foreign function interface declaration}
* *
************************************************************************
-}
-- 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
-- | Located Foreign Declaration
type LForeignDecl pass = Located (ForeignDecl pass)
-- | Foreign Declaration
data ForeignDecl pass
= ForeignImport
{ fd_name :: Located (IdP pass) -- defines this name
, fd_sig_ty :: LHsSigType pass -- sig_ty
, fd_co :: PostTc pass Coercion -- rep_ty ~ sig_ty
, fd_fi :: ForeignImport }
| ForeignExport
{ fd_name :: Located (IdP pass) -- uses this name
, fd_sig_ty :: LHsSigType pass -- sig_ty
, fd_co :: PostTc pass Coercion -- rep_ty ~ sig_ty
, fd_fe :: ForeignExport }
-- ^
-- - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnForeign',
-- 'ApiAnnotation.AnnImport','ApiAnnotation.AnnExport',
-- 'ApiAnnotation.AnnDcolon'
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance (DataId pass) => Data (ForeignDecl pass)
{-
In both ForeignImport and ForeignExport:
sig_ty is the type given in the Haskell code
rep_ty is the representation for this type, i.e. with newtypes
coerced away and type functions evaluated.
Thus if the declaration is valid, then rep_ty will only use types
such as Int and IO that we know how to make foreign calls with.
-}
noForeignImportCoercionYet :: PlaceHolder
noForeignImportCoercionYet = PlaceHolder
noForeignExportCoercionYet :: PlaceHolder
noForeignExportCoercionYet = PlaceHolder
-- 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 (Located CCallConv) -- ccall or stdcall
(Located Safety) -- interruptible, safe or unsafe
(Maybe Header) -- name of C header
CImportSpec -- details of the C entity
(Located SourceText) -- original source text for
-- the C entity
deriving Data
-- 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.)
deriving Data
-- specification of an externally exported entity in dependence on the calling
-- convention
--
data ForeignExport = CExport (Located CExportSpec) -- contains the calling
-- convention
(Located SourceText) -- original source text for
-- the C entity
deriving Data
-- pretty printing of foreign declarations
--
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (ForeignDecl pass) where
ppr (ForeignImport { fd_name = n, fd_sig_ty = ty, fd_fi = fimport })
= hang (text "foreign import" <+> ppr fimport <+> ppr n)
2 (dcolon <+> ppr ty)
ppr (ForeignExport { fd_name = n, fd_sig_ty = ty, fd_fe = fexport }) =
hang (text "foreign export" <+> ppr fexport <+> ppr n)
2 (dcolon <+> ppr ty)
instance Outputable ForeignImport where
ppr (CImport cconv safety mHeader spec (L _ srcText)) =
ppr cconv <+> ppr safety
<+> pprWithSourceText srcText (pprCEntity spec "")
where
pp_hdr = case mHeader of
Nothing -> empty
Just (Header _ header) -> ftext header
pprCEntity (CLabel lbl) _ =
doubleQuotes $ text "static" <+> pp_hdr <+> char '&' <> ppr lbl
pprCEntity (CFunction (StaticTarget st _lbl _ isFun)) src =
if dqNeeded then doubleQuotes ce else empty
where
dqNeeded = (take 6 src == "static")
|| isJust mHeader
|| not isFun
|| st /= NoSourceText
ce =
-- We may need to drop leading spaces first
(if take 6 src == "static" then text "static" else empty)
<+> pp_hdr
<+> (if isFun then empty else text "value")
<+> (pprWithSourceText st empty)
pprCEntity (CFunction DynamicTarget) _ =
doubleQuotes $ text "dynamic"
pprCEntity CWrapper _ = doubleQuotes $ text "wrapper"
instance Outputable ForeignExport where
ppr (CExport (L _ (CExportStatic _ lbl cconv)) _) =
ppr cconv <+> char '"' <> ppr lbl <> char '"'
{-
************************************************************************
* *
\subsection{Transformation rules}
* *
************************************************************************
-}
-- | Located Rule Declarations
type LRuleDecls pass = Located (RuleDecls pass)
-- Note [Pragma source text] in BasicTypes
-- | Rule Declarations
data RuleDecls pass = HsRules { rds_src :: SourceText
, rds_rules :: [LRuleDecl pass] }
deriving instance (DataId pass) => Data (RuleDecls pass)
-- | Located Rule Declaration
type LRuleDecl pass = Located (RuleDecl pass)
-- | Rule Declaration
data RuleDecl pass
= HsRule -- Source rule
(Located (SourceText,RuleName)) -- Rule name
-- Note [Pragma source text] in BasicTypes
Activation
[LRuleBndr pass] -- Forall'd vars; after typechecking this
-- includes tyvars
(Located (HsExpr pass)) -- LHS
(PostRn pass NameSet) -- Free-vars from the LHS
(Located (HsExpr pass)) -- RHS
(PostRn pass NameSet) -- Free-vars from the RHS
-- ^
-- - 'ApiAnnotation.AnnKeywordId' :
-- 'ApiAnnotation.AnnOpen','ApiAnnotation.AnnTilde',
-- 'ApiAnnotation.AnnVal',
-- 'ApiAnnotation.AnnClose',
-- 'ApiAnnotation.AnnForall','ApiAnnotation.AnnDot',
-- 'ApiAnnotation.AnnEqual',
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance (DataId pass) => Data (RuleDecl pass)
flattenRuleDecls :: [LRuleDecls pass] -> [LRuleDecl pass]
flattenRuleDecls decls = concatMap (rds_rules . unLoc) decls
-- | Located Rule Binder
type LRuleBndr pass = Located (RuleBndr pass)
-- | Rule Binder
data RuleBndr pass
= RuleBndr (Located (IdP pass))
| RuleBndrSig (Located (IdP pass)) (LHsSigWcType pass)
-- ^
-- - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
-- 'ApiAnnotation.AnnDcolon','ApiAnnotation.AnnClose'
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance (DataId pass) => Data (RuleBndr pass)
collectRuleBndrSigTys :: [RuleBndr pass] -> [LHsSigWcType pass]
collectRuleBndrSigTys bndrs = [ty | RuleBndrSig _ ty <- bndrs]
pprFullRuleName :: Located (SourceText, RuleName) -> SDoc
pprFullRuleName (L _ (st, n)) = pprWithSourceText st (doubleQuotes $ ftext n)
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (RuleDecls pass) where
ppr (HsRules st rules)
= pprWithSourceText st (text "{-# RULES")
<+> vcat (punctuate semi (map ppr rules)) <+> text "#-}"
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (RuleDecl pass) where
ppr (HsRule name act ns lhs _fv_lhs rhs _fv_rhs)
= sep [pprFullRuleName name <+> ppr act,
nest 4 (pp_forall <+> pprExpr (unLoc lhs)),
nest 6 (equals <+> pprExpr (unLoc rhs)) ]
where
pp_forall | null ns = empty
| otherwise = forAllLit <+> fsep (map ppr ns) <> dot
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (RuleBndr pass) where
ppr (RuleBndr name) = ppr name
ppr (RuleBndrSig name ty) = parens (ppr name <> dcolon <> ppr ty)
{-
************************************************************************
* *
\subsection{Vectorisation declarations}
* *
************************************************************************
A vectorisation pragma, one of
{-# VECTORISE f = closure1 g (scalar_map g) #-}
{-# VECTORISE SCALAR f #-}
{-# NOVECTORISE f #-}
{-# VECTORISE type T = ty #-}
{-# VECTORISE SCALAR type T #-}
-}
-- | Located Vectorise Declaration
type LVectDecl pass = Located (VectDecl pass)
-- | Vectorise Declaration
data VectDecl pass
= HsVect
SourceText -- Note [Pragma source text] in BasicTypes
(Located (IdP pass))
(LHsExpr pass)
-- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
-- 'ApiAnnotation.AnnEqual','ApiAnnotation.AnnClose'
-- For details on above see note [Api annotations] in ApiAnnotation
| HsNoVect
SourceText -- Note [Pragma source text] in BasicTypes
(Located (IdP pass))
-- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
-- 'ApiAnnotation.AnnClose'
-- For details on above see note [Api annotations] in ApiAnnotation
| HsVectTypeIn -- pre type-checking
SourceText -- Note [Pragma source text] in BasicTypes
Bool -- 'TRUE' => SCALAR declaration
(Located (IdP pass))
(Maybe (Located (IdP pass))) -- 'Nothing' => no right-hand side
-- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
-- 'ApiAnnotation.AnnType','ApiAnnotation.AnnClose',
-- 'ApiAnnotation.AnnEqual'
-- For details on above see note [Api annotations] in ApiAnnotation
| HsVectTypeOut -- post type-checking
Bool -- 'TRUE' => SCALAR declaration
TyCon
(Maybe TyCon) -- 'Nothing' => no right-hand side
| HsVectClassIn -- pre type-checking
SourceText -- Note [Pragma source text] in BasicTypes
(Located (IdP pass))
-- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
-- 'ApiAnnotation.AnnClass','ApiAnnotation.AnnClose',
-- For details on above see note [Api annotations] in ApiAnnotation
| HsVectClassOut -- post type-checking
Class
| HsVectInstIn -- pre type-checking (always SCALAR) !!!FIXME: should be superfluous now
(LHsSigType pass)
| HsVectInstOut -- post type-checking (always SCALAR) !!!FIXME: should be superfluous now
ClsInst
deriving instance (DataId pass) => Data (VectDecl pass)
lvectDeclName :: NamedThing (IdP pass) => LVectDecl pass -> Name
lvectDeclName (L _ (HsVect _ (L _ name) _)) = getName name
lvectDeclName (L _ (HsNoVect _ (L _ name))) = getName name
lvectDeclName (L _ (HsVectTypeIn _ _ (L _ name) _)) = getName name
lvectDeclName (L _ (HsVectTypeOut _ tycon _)) = getName tycon
lvectDeclName (L _ (HsVectClassIn _ (L _ name))) = getName name
lvectDeclName (L _ (HsVectClassOut cls)) = getName cls
lvectDeclName (L _ (HsVectInstIn _))
= panic "HsDecls.lvectDeclName: HsVectInstIn"
lvectDeclName (L _ (HsVectInstOut _))
= panic "HsDecls.lvectDeclName: HsVectInstOut"
lvectInstDecl :: LVectDecl pass -> Bool
lvectInstDecl (L _ (HsVectInstIn _)) = True
lvectInstDecl (L _ (HsVectInstOut _)) = True
lvectInstDecl _ = False
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (VectDecl pass) where
ppr (HsVect _ v rhs)
= sep [text "{-# VECTORISE" <+> ppr v,
nest 4 $
pprExpr (unLoc rhs) <+> text "#-}" ]
ppr (HsNoVect _ v)
= sep [text "{-# NOVECTORISE" <+> ppr v <+> text "#-}" ]
ppr (HsVectTypeIn _ False t Nothing)
= sep [text "{-# VECTORISE type" <+> ppr t <+> text "#-}" ]
ppr (HsVectTypeIn _ False t (Just t'))
= sep [text "{-# VECTORISE type" <+> ppr t, text "=", ppr t', text "#-}" ]
ppr (HsVectTypeIn _ True t Nothing)
= sep [text "{-# VECTORISE SCALAR type" <+> ppr t <+> text "#-}" ]
ppr (HsVectTypeIn _ True t (Just t'))
= sep [text "{-# VECTORISE SCALAR type" <+> ppr t, text "=", ppr t', text "#-}" ]
ppr (HsVectTypeOut False t Nothing)
= sep [text "{-# VECTORISE type" <+> ppr t <+> text "#-}" ]
ppr (HsVectTypeOut False t (Just t'))
= sep [text "{-# VECTORISE type" <+> ppr t, text "=", ppr t', text "#-}" ]
ppr (HsVectTypeOut True t Nothing)
= sep [text "{-# VECTORISE SCALAR type" <+> ppr t <+> text "#-}" ]
ppr (HsVectTypeOut True t (Just t'))
= sep [text "{-# VECTORISE SCALAR type" <+> ppr t, text "=", ppr t', text "#-}" ]
ppr (HsVectClassIn _ c)
= sep [text "{-# VECTORISE class" <+> ppr c <+> text "#-}" ]
ppr (HsVectClassOut c)
= sep [text "{-# VECTORISE class" <+> ppr c <+> text "#-}" ]
ppr (HsVectInstIn ty)
= sep [text "{-# VECTORISE SCALAR instance" <+> ppr ty <+> text "#-}" ]
ppr (HsVectInstOut i)
= sep [text "{-# VECTORISE SCALAR instance" <+> ppr i <+> text "#-}" ]
{-
************************************************************************
* *
\subsection[DocDecl]{Document comments}
* *
************************************************************************
-}
-- | Located Documentation comment Declaration
type LDocDecl = Located (DocDecl)
-- | Documentation comment Declaration
data DocDecl
= DocCommentNext HsDocString
| DocCommentPrev HsDocString
| DocCommentNamed String HsDocString
| DocGroup Int HsDocString
deriving Data
-- Okay, I need to reconstruct the document comments, but for now:
instance Outputable DocDecl where
ppr _ = text "<document comment>"
docDeclDoc :: DocDecl -> HsDocString
docDeclDoc (DocCommentNext d) = d
docDeclDoc (DocCommentPrev d) = d
docDeclDoc (DocCommentNamed _ d) = d
docDeclDoc (DocGroup _ d) = d
{-
************************************************************************
* *
\subsection[DeprecDecl]{Deprecations}
* *
************************************************************************
We use exported entities for things to deprecate.
-}
-- | Located Warning Declarations
type LWarnDecls pass = Located (WarnDecls pass)
-- Note [Pragma source text] in BasicTypes
-- | Warning pragma Declarations
data WarnDecls pass = Warnings { wd_src :: SourceText
, wd_warnings :: [LWarnDecl pass]
}
deriving instance (DataId pass) => Data (WarnDecls pass)
-- | Located Warning pragma Declaration
type LWarnDecl pass = Located (WarnDecl pass)
-- | Warning pragma Declaration
data WarnDecl pass = Warning [Located (IdP pass)] WarningTxt
deriving instance (DataId pass) => Data (WarnDecl pass)
instance OutputableBndr (IdP pass) => Outputable (WarnDecls pass) where
ppr (Warnings (SourceText src) decls)
= text src <+> vcat (punctuate comma (map ppr decls)) <+> text "#-}"
ppr (Warnings NoSourceText _decls) = panic "WarnDecls"
instance OutputableBndr (IdP pass) => Outputable (WarnDecl pass) where
ppr (Warning thing txt)
= hsep ( punctuate comma (map ppr thing))
<+> ppr txt
{-
************************************************************************
* *
\subsection[AnnDecl]{Annotations}
* *
************************************************************************
-}
-- | Located Annotation Declaration
type LAnnDecl pass = Located (AnnDecl pass)
-- | Annotation Declaration
data AnnDecl pass = HsAnnotation
SourceText -- Note [Pragma source text] in BasicTypes
(AnnProvenance (IdP pass)) (Located (HsExpr pass))
-- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
-- 'ApiAnnotation.AnnType'
-- 'ApiAnnotation.AnnModule'
-- 'ApiAnnotation.AnnClose'
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance (DataId pass) => Data (AnnDecl pass)
instance (SourceTextX pass, OutputableBndrId pass)
=> Outputable (AnnDecl pass) where
ppr (HsAnnotation _ provenance expr)
= hsep [text "{-#", pprAnnProvenance provenance, pprExpr (unLoc expr), text "#-}"]
-- | Annotation Provenance
data AnnProvenance name = ValueAnnProvenance (Located name)
| TypeAnnProvenance (Located name)
| ModuleAnnProvenance
deriving instance Functor AnnProvenance
deriving instance Foldable AnnProvenance
deriving instance Traversable AnnProvenance
deriving instance (Data pass) => Data (AnnProvenance pass)
annProvenanceName_maybe :: AnnProvenance name -> Maybe name
annProvenanceName_maybe (ValueAnnProvenance (L _ name)) = Just name
annProvenanceName_maybe (TypeAnnProvenance (L _ name)) = Just name
annProvenanceName_maybe ModuleAnnProvenance = Nothing
pprAnnProvenance :: OutputableBndr name => AnnProvenance name -> SDoc
pprAnnProvenance ModuleAnnProvenance = text "ANN module"
pprAnnProvenance (ValueAnnProvenance (L _ name))
= text "ANN" <+> ppr name
pprAnnProvenance (TypeAnnProvenance (L _ name))
= text "ANN type" <+> ppr name
{-
************************************************************************
* *
\subsection[RoleAnnot]{Role annotations}
* *
************************************************************************
-}
-- | Located Role Annotation Declaration
type LRoleAnnotDecl pass = Located (RoleAnnotDecl pass)
-- See #8185 for more info about why role annotations are
-- top-level declarations
-- | Role Annotation Declaration
data RoleAnnotDecl pass
= RoleAnnotDecl (Located (IdP pass)) -- type constructor
[Located (Maybe Role)] -- optional annotations
-- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnType',
-- 'ApiAnnotation.AnnRole'
-- For details on above see note [Api annotations] in ApiAnnotation
deriving instance (DataId pass) => Data (RoleAnnotDecl pass)
instance OutputableBndr (IdP pass) => Outputable (RoleAnnotDecl pass) where
ppr (RoleAnnotDecl ltycon roles)
= text "type role" <+> ppr ltycon <+>
hsep (map (pp_role . unLoc) roles)
where
pp_role Nothing = underscore
pp_role (Just r) = ppr r
roleAnnotDeclName :: RoleAnnotDecl pass -> (IdP pass)
roleAnnotDeclName (RoleAnnotDecl (L _ name) _) = name