diff options
Diffstat (limited to 'compiler/parser/Parser.y')
| -rw-r--r-- | compiler/parser/Parser.y | 222 |
1 files changed, 98 insertions, 124 deletions
diff --git a/compiler/parser/Parser.y b/compiler/parser/Parser.y index bbde989293..06be056575 100644 --- a/compiler/parser/Parser.y +++ b/compiler/parser/Parser.y @@ -59,7 +59,7 @@ import BasicTypes -- compiler/types import Type ( funTyCon ) -import Kind ( Kind, liftedTypeKind, unliftedTypeKind, mkArrowKind ) +import Kind ( Kind ) import Class ( FunDep ) -- compiler/parser @@ -73,10 +73,11 @@ import TcEvidence ( emptyTcEvBinds ) -- compiler/prelude import ForeignCall -import TysPrim ( liftedTypeKindTyConName, eqPrimTyCon ) +import TysPrim ( eqPrimTyCon ) +import PrelNames ( eqTyCon_RDR ) import TysWiredIn ( unitTyCon, unitDataCon, tupleTyCon, tupleDataCon, nilDataCon, unboxedUnitTyCon, unboxedUnitDataCon, - listTyCon_RDR, parrTyCon_RDR, consDataCon_RDR, eqTyCon_RDR ) + listTyCon_RDR, parrTyCon_RDR, consDataCon_RDR ) -- compiler/utils import Util ( looksLikePackageName ) @@ -84,9 +85,9 @@ import Prelude } -{- Last updated: 31 Jul 2015 +{- Last updated: 18 Nov 2015 -Conflicts: 47 shift/reduce +Conflicts: 36 shift/reduce If you modify this parser and add a conflict, please update this comment. You can learn more about the conflicts by passing 'happy' the -i flag: @@ -127,35 +128,26 @@ state 46 contains 2 shift/reduce conflicts. ------------------------------------------------------------------------------- -state 50 contains 11 shift/reduce conflicts. +state 50 contains 1 shift/reduce conflict. - context -> btype . (rule 282) - *** type -> btype . (rule 283) - type -> btype . qtyconop type (rule 284) - type -> btype . tyvarop type (rule 285) - type -> btype . '->' ctype (rule 286) - type -> btype . SIMPLEQUOTE qconop type (rule 287) - type -> btype . SIMPLEQUOTE varop type (rule 288) - btype -> btype . atype (rule 299) + context -> btype . (rule 295) + *** type -> btype . (rule 297) + type -> btype . '->' ctype (rule 298) - Conflicts: ':' '->' '-' '!' '*' '.' '`' VARSYM CONSYM QVARSYM QCONSYM + Conflicts: '->' -Example of ambiguity: 'e :: a `b` c'; does this mean - (e::a) `b` c, or - (e :: (a `b` c)) +------------------------------------------------------------------------------- + +state 51 contains 9 shift/reduce conflicts. + + *** btype -> tyapps . (rule 303) + tyapps -> tyapps . tyapp (rule 307) -The case for '->' involves view patterns rather than type operators: - 'case v of { x :: T -> T ... } ' - Which of these two is intended? - case v of - (x::T) -> T -- Rhs is T - or - case v of - (x::T -> T) -> .. -- Rhs is ... + Conflicts: ':' '-' '!' '.' '`' VARSYM CONSYM QVARSYM QCONSYM ------------------------------------------------------------------------------- -state 119 contains 15 shift/reduce conflicts. +state 132 contains 14 shift/reduce conflicts. exp -> infixexp . '::' sigtype (rule 416) exp -> infixexp . '-<' exp (rule 417) @@ -165,7 +157,7 @@ state 119 contains 15 shift/reduce conflicts. *** exp -> infixexp . (rule 421) infixexp -> infixexp . qop exp10 (rule 423) - Conflicts: ':' '::' '-' '!' '*' '-<' '>-' '-<<' '>>-' + Conflicts: ':' '::' '-' '!' '-<' '>-' '-<<' '>>-' '.' '`' VARSYM CONSYM QVARSYM QCONSYM Examples of ambiguity: @@ -180,7 +172,7 @@ Shift parses as (per longest-parse rule): ------------------------------------------------------------------------------- -state 279 contains 1 shift/reduce conflicts. +state 292 contains 1 shift/reduce conflicts. rule -> STRING . rule_activation rule_forall infixexp '=' exp (rule 215) @@ -198,23 +190,18 @@ a rule instructing how to rewrite the expression '[0] f'. ------------------------------------------------------------------------------- -state 288 contains 11 shift/reduce conflicts. +state 301 contains 1 shift/reduce conflict. - *** type -> btype . (rule 283) - type -> btype . qtyconop type (rule 284) - type -> btype . tyvarop type (rule 285) - type -> btype . '->' ctype (rule 286) - type -> btype . SIMPLEQUOTE qconop type (rule 287) - type -> btype . SIMPLEQUOTE varop type (rule 288) - btype -> btype . atype (rule 299) + *** type -> btype . (rule 297) + type -> btype . '->' ctype (rule 298) - Conflicts: ':' '->' '-' '!' '*' '.' '`' VARSYM CONSYM QVARSYM QCONSYM + Conflict: '->' -Same as State 50, but minus the context productions. +Same as state 50 but without contexts. ------------------------------------------------------------------------------- -state 324 contains 1 shift/reduce conflicts. +state 337 contains 1 shift/reduce conflicts. tup_exprs -> commas . tup_tail (rule 505) sysdcon_nolist -> '(' commas . ')' (rule 616) @@ -229,7 +216,7 @@ if -XTupleSections is not specified. ------------------------------------------------------------------------------- -state 376 contains 1 shift/reduce conflicts. +state 388 contains 1 shift/reduce conflicts. tup_exprs -> commas . tup_tail (rule 505) sysdcon_nolist -> '(#' commas . '#)' (rule 618) @@ -241,20 +228,18 @@ Same as State 324 for unboxed tuples. ------------------------------------------------------------------------------- -state 404 contains 1 shift/reduce conflicts. +state 460 contains 1 shift/reduce conflict. - exp10 -> 'let' binds . 'in' exp (rule 425) - exp10 -> 'let' binds . 'in' error (rule 440) - exp10 -> 'let' binds . error (rule 441) - *** qual -> 'let' binds . (rule 579) + oqtycon -> '(' qtyconsym . ')' (rule 621) + *** qtyconop -> qtyconsym . (rule 628) - Conflict: error + Conflict: ')' TODO: Why? ------------------------------------------------------------------------------- -state 633 contains 1 shift/reduce conflicts. +state 635 contains 1 shift/reduce conflicts. *** aexp2 -> ipvar . (rule 466) dbind -> ipvar . '=' exp (rule 590) @@ -269,7 +254,7 @@ sensible meaning, namely the lhs of an implicit binding. ------------------------------------------------------------------------------- -state 699 contains 1 shift/reduce conflicts. +state 702 contains 1 shift/reduce conflicts. rule -> STRING rule_activation . rule_forall infixexp '=' exp (rule 215) @@ -286,7 +271,7 @@ doesn't include 'forall'. ------------------------------------------------------------------------------- -state 950 contains 1 shift/reduce conflicts. +state 930 contains 1 shift/reduce conflicts. transformqual -> 'then' 'group' . 'using' exp (rule 528) transformqual -> 'then' 'group' . 'by' exp 'using' exp (rule 529) @@ -294,6 +279,16 @@ state 950 contains 1 shift/reduce conflicts. Conflict: 'by' +------------------------------------------------------------------------------- + +state 1270 contains 1 shift/reduce conflict. + + *** atype -> tyvar . (rule 314) + tv_bndr -> '(' tyvar . '::' kind ')' (rule 346) + + Conflict: '::' + +TODO: Why? ------------------------------------------------------------------------------- -- API Annotations @@ -413,7 +408,6 @@ output it generates. '=>' { L _ (ITdarrow _) } '-' { L _ ITminus } '!' { L _ ITbang } - '*' { L _ (ITstar _) } '-<' { L _ (ITlarrowtail _) } -- for arrow notation '>-' { L _ (ITrarrowtail _) } -- for arrow notation '-<<' { L _ (ITLarrowtail _) } -- for arrow notation @@ -1606,12 +1600,22 @@ ctypedoc :: { LHsType RdrName } -- but not f :: ?x::Int => blah -- See Note [Parsing ~] context :: { LHsContext RdrName } - : btype {% do { (anns,ctx) <- checkContext (splitTilde $1) + : btype {% do { (anns,ctx) <- checkContext $1 ; if null (unLoc ctx) then addAnnotation (gl $1) AnnUnit (gl $1) else return () ; ams ctx anns } } + +context_no_ops :: { LHsContext RdrName } + : btype_no_ops {% do { let { ty = splitTilde $1 } + ; (anns,ctx) <- checkContext ty + ; if null (unLoc ctx) + then addAnnotation (gl ty) AnnUnit (gl ty) + else return () + ; ams ctx anns + } } + {- Note [GADT decl discards annotations] ~~~~~~~~~~~~~~~~~~~~~ The type production for @@ -1628,40 +1632,49 @@ the top-level annotation will be disconnected. Hence for this specific case it is connected to the first type too. -} --- See Note [Parsing ~] type :: { LHsType RdrName } - : btype { splitTilde $1 } - | btype qtyconop type { sLL $1 $> $ mkHsOpTy $1 $2 $3 } - | btype tyvarop type { sLL $1 $> $ mkHsOpTy $1 $2 $3 } - | btype '->' ctype {% ams $1 [mu AnnRarrow $2] -- See note [GADT decl discards annotations] - >> ams (sLL $1 $> $ HsFunTy (splitTilde $1) $3) - [mu AnnRarrow $2] } - | btype SIMPLEQUOTE qconop type {% ams (sLL $1 $> $ mkHsOpTy $1 $3 $4) - [mj AnnSimpleQuote $2] } - | btype SIMPLEQUOTE varop type {% ams (sLL $1 $> $ mkHsOpTy $1 $3 $4) - [mj AnnSimpleQuote $2] } --- See Note [Parsing ~] + : btype { $1 } + | btype '->' ctype {% ams $1 [mu AnnRarrow $2] -- See note [GADT decl discards annotations] + >> ams (sLL $1 $> $ HsFunTy $1 $3) + [mu AnnRarrow $2] } + + typedoc :: { LHsType RdrName } - : btype { splitTilde $1 } - | btype docprev { sLL $1 $> $ HsDocTy (splitTilde $1) $2 } - | btype qtyconop type { sLL $1 $> $ mkHsOpTy $1 $2 $3 } - | btype qtyconop type docprev { sLL $1 $> $ HsDocTy (L (comb3 $1 $2 $3) (mkHsOpTy $1 $2 $3)) $4 } - | btype tyvarop type { sLL $1 $> $ mkHsOpTy $1 $2 $3 } - | btype tyvarop type docprev { sLL $1 $> $ HsDocTy (L (comb3 $1 $2 $3) (mkHsOpTy $1 $2 $3)) $4 } - | btype '->' ctypedoc {% ams (sLL $1 $> $ HsFunTy (splitTilde $1) $3) + : btype { $1 } + | btype docprev { sLL $1 $> $ HsDocTy $1 $2 } + | btype '->' ctypedoc {% ams (sLL $1 $> $ HsFunTy $1 $3) [mu AnnRarrow $2] } - | btype docprev '->' ctypedoc {% ams (sLL $1 $> $ HsFunTy (L (comb2 (splitTilde $1) $2) - (HsDocTy $1 $2)) $4) + | btype docprev '->' ctypedoc {% ams (sLL $1 $> $ + HsFunTy (L (comb2 $1 $2) (HsDocTy $1 $2)) + $4) [mu AnnRarrow $3] } - | btype SIMPLEQUOTE qconop type {% ams (sLL $1 $> $ mkHsOpTy $1 $3 $4) - [mj AnnSimpleQuote $2] } - | btype SIMPLEQUOTE varop type {% ams (sLL $1 $> $ mkHsOpTy $1 $3 $4) - [mj AnnSimpleQuote $2] } +-- See Note [Parsing ~] btype :: { LHsType RdrName } - : btype atype { sLL $1 $> $ HsAppTy $1 $2 } + : tyapps { sL1 $1 $ HsAppsTy (splitTildeApps (reverse (unLoc $1))) } + +-- Used for parsing Haskell98-style data constructors, +-- in order to forbid the blasphemous +-- > data Foo = Int :+ Char :* Bool +-- See also Note [Parsing data constructors is hard]. +btype_no_ops :: { LHsType RdrName } + : btype_no_ops atype { sLL $1 $> $ HsAppTy $1 $2 } | atype { $1 } +tyapps :: { Located [HsAppType RdrName] } -- NB: This list is reversed + : tyapp { sL1 $1 [unLoc $1] } + | tyapps tyapp { sLL $1 $> $ (unLoc $2) : (unLoc $1) } + +-- See Note [HsAppsTy] in HsTypes +tyapp :: { Located (HsAppType RdrName) } + : atype { sL1 $1 $ HsAppPrefix $1 } + | qtyconop { sL1 $1 $ HsAppInfix $1 } + | tyvarop { sL1 $1 $ HsAppInfix $1 } + | SIMPLEQUOTE qconop {% ams (sLL $1 $> $ HsAppInfix $2) + [mj AnnSimpleQuote $1] } + | SIMPLEQUOTE varop {% ams (sLL $1 $> $ HsAppInfix $2) + [mj AnnSimpleQuote $1] } + atype :: { LHsType RdrName } : ntgtycon { sL1 $1 (HsTyVar $1) } -- Not including unit tuples | tyvar {% do { nwc <- namedWildCardsEnabled -- (See Note [Unit tuples]) @@ -1797,37 +1810,7 @@ turn them into HsEqTy's. -- Kinds kind :: { LHsKind RdrName } - : bkind { $1 } - | bkind '->' kind {% ams (sLL $1 $> $ HsFunTy $1 $3) - [mu AnnRarrow $2] } - -bkind :: { LHsKind RdrName } - : akind { $1 } - | bkind akind { sLL $1 $> $ HsAppTy $1 $2 } - -akind :: { LHsKind RdrName } - : '*' {% ams (sL1 $1 $ HsTyVar (sL1 $1 (nameRdrName liftedTypeKindTyConName))) - [mu AnnStar $1] } - | '(' kind ')' {% ams (sLL $1 $> $ HsParTy $2) - [mop $1,mcp $3] } - | pkind { $1 } - | tyvar { sL1 $1 $ HsTyVar $1 } - -pkind :: { LHsKind RdrName } -- promoted type, see Note [Promotion] - : qtycon { sL1 $1 $ HsTyVar $1 } - | '(' ')' {% ams (sLL $1 $> $ HsTyVar $ (sLL $1 $> $ getRdrName unitTyCon)) - [mop $1,mcp $2] } - | '(' kind ',' comma_kinds1 ')' - {% addAnnotation (gl $2) AnnComma (gl $3) >> - ams (sLL $1 $> $ HsTupleTy HsBoxedTuple ( $2 : $4)) - [mop $1,mcp $5] } - | '[' kind ']' {% ams (sLL $1 $> $ HsListTy $2) - [mos $1,mcs $3] } - -comma_kinds1 :: { [LHsKind RdrName] } - : kind { [$1] } - | kind ',' comma_kinds1 {% addAnnotation (gl $1) AnnComma (gl $2) - >> return ($1 : $3) } + : ctype { $1 } {- Note [Promotion] ~~~~~~~~~~~~~~~~ @@ -1840,12 +1823,6 @@ few reasons: 2. if one day we merge types and kinds, tick would mean look in DataName 3. we don't have a kind namespace anyway -- Syntax of explicit kind polymorphism (IA0_TODO: not yet implemented) -Kind abstraction is implicit. We write -> data SList (s :: k -> *) (as :: [k]) where ... -because it looks like what we do in terms -> id (x :: a) = x - - Name resolution When the user write Zero instead of 'Zero in types, we parse it a HsTyVar ("Zero", TcClsName) instead of HsTyVar ("Zero", DataName). We @@ -1922,7 +1899,7 @@ constrs1 :: { Located [LConDecl RdrName] } | constr { sL1 $1 [$1] } constr :: { LConDecl RdrName } - : maybe_docnext forall context '=>' constr_stuff maybe_docprev + : maybe_docnext forall context_no_ops '=>' constr_stuff maybe_docprev {% ams (let (con,details) = unLoc $5 in addConDoc (L (comb4 $2 $3 $4 $5) (mkConDeclH98 con (snd $ unLoc $2) $3 details)) @@ -1941,16 +1918,17 @@ forall :: { Located ([AddAnn], Maybe [LHsTyVarBndr RdrName]) } constr_stuff :: { Located (Located RdrName, HsConDeclDetails RdrName) } -- see Note [Parsing data constructors is hard] - : btype {% splitCon $1 >>= return.sLL $1 $> } - | btype conop btype { sLL $1 $> ($2, InfixCon $1 $3) } + : btype_no_ops {% do { c <- splitCon $1 + ; return $ sLL $1 $> c } } + | btype_no_ops conop btype_no_ops { sLL $1 $> ($2, InfixCon (splitTilde $1) $3) } {- Note [Parsing data constructors is hard] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ We parse the constructor declaration C t1 t2 -as a btype (treating C as a type constructor) and then convert C to be +as a btype_no_ops (treating C as a type constructor) and then convert C to be a data constructor. Reason: it might continue like this: - C t1 t2 %: D Int + C t1 t2 :% D Int in which case C really would be a type constructor. We can't resolve this ambiguity till we come across the constructor oprerator :% (or not, more usually) -} @@ -2931,8 +2909,6 @@ tyconsym :: { Located RdrName } : CONSYM { sL1 $1 $! mkUnqual tcClsName (getCONSYM $1) } | VARSYM { sL1 $1 $! mkUnqual tcClsName (getVARSYM $1) } | ':' { sL1 $1 $! consDataCon_RDR } - | '*' {% ams (sL1 $1 $! mkUnqual tcClsName (fsLit "*")) - [mu AnnStar $1] } | '-' { sL1 $1 $! mkUnqual tcClsName (fsLit "-") } @@ -3070,7 +3046,6 @@ special_id special_sym :: { Located FastString } special_sym : '!' {% ams (sL1 $1 (fsLit "!")) [mj AnnBang $1] } | '.' { sL1 $1 (fsLit ".") } - | '*' {% ams (sL1 $1 (fsLit "*")) [mu AnnStar $1] } ----------------------------------------------------------------------------- -- Data constructors @@ -3240,7 +3215,6 @@ isUnicode (L _ (ITdcolon iu)) = iu == UnicodeSyntax isUnicode (L _ (ITlarrow iu)) = iu == UnicodeSyntax isUnicode (L _ (ITrarrow iu)) = iu == UnicodeSyntax isUnicode (L _ (ITrarrow iu)) = iu == UnicodeSyntax -isUnicode (L _ (ITstar iu)) = iu == UnicodeSyntax isUnicode (L _ (ITlarrowtail iu)) = iu == UnicodeSyntax isUnicode (L _ (ITrarrowtail iu)) = iu == UnicodeSyntax isUnicode (L _ (ITLarrowtail iu)) = iu == UnicodeSyntax |