ParseTerm.hs revision 737526b54e46fa1a76c4b5e793124ee765adef6c
$Id$
Authors: Christian Maeder
Year: 2002
parser for HasCASL kind, types, terms and pattern/equations
-}
module ParseTerm where
import Id
import Keywords
import Lexer
import Token(formula_ops)
import HToken
import As
import Parsec
import AS_Annotation
import Anno_Parser(annotationL)
noQuMark s = try $ asKey s << notFollowedBy (char '?')
colonT = noQuMark colonS
lessT = asKey lessS
equalT = asKey equalS
asT = asKey asP
plusT = asKey plusS
minusT = asKey minusS
dotT = try(asKey dotS <|> asKey cDot) <?> "dot"
crossT = try(asKey prodS <|> asKey timesS) <?> "cross"
barT = asKey barS
quMarkT = asKey quMark
qColonT = asKey (colonS++quMark)
forallT = asKey forallS
-----------------------------------------------------------------------------
-- kind
-----------------------------------------------------------------------------
-- universe is just a special className ("Type")
parseClass = fmap ClassName className
<|>
do o <- oParenT
(cs, ps) <- parseClass `separatedBy` commaT
c <- cParenT
return (Intersection cs (toPos o ps c))
extClass = do c <- parseClass
do s <- plusT
return (ExtClass c CoVar (tokPos s))
<|>
do s <- minusT
return (ExtClass c ContraVar (tokPos s))
<|> return (ExtClass c InVar nullPos)
isClass (ExtClass _ InVar _) = True
isClass _ = False
classOf (ExtClass c _ _) = c
prodClass = do (cs, ps) <- extClass `separatedBy` crossT
return (ProdClass cs (map tokPos ps))
kind = kindOrClass [] []
kindOrClass os ps = do c@(ProdClass cs _) <- prodClass
if length cs == 1 && isClass (head cs)
then curriedKind (os++[c]) ps
<|> return (Kind os (classOf (head cs))
(map tokPos ps))
else curriedKind (os++[c]) ps
curriedKind os ps = do a <- asKey funS
kindOrClass os (ps++[a])
-----------------------------------------------------------------------------
-- type
-----------------------------------------------------------------------------
-- a parsed type may also be interpreted as a kind (by the mixfix analysis)
typeToken :: GenParser Char st Type
typeToken = fmap TypeToken (pToken (scanWords <|> placeS <|>
reserved (hascasl_type_ops ++
formula_ops ++
hascasl_reserved_ops)
scanAnySigns))
braces p c = bracketParser p oBraceT cBraceT commaT c
-- [...] may contain types or ids
idToken b = pToken (scanQuotedChar <|> scanDotWords
<|> scanDigit <|> scanWords <|> placeS <|>
reserved ((if b then formula_ops else funS:formula_ops)
++ hascasl_reserved_ops)
scanAnySigns)
primTypeOrId = fmap TypeToken (idToken True)
<|> braces typeOrId (BracketType Braces)
<|> brackets typeOrId (BracketType Squares)
<|> bracketParser typeOrId oParenT cParenT commaT
(BracketType Parens)
typeOrId = do ts <- many1 primTypeOrId
let t = if length ts == 1 then head ts
else MixfixType ts
in
kindAnno t
<|>
return(t)
kindAnno t = do c <- colonT
k <- kind
return (KindedType t k (tokPos c))
primType = typeToken
<|> bracketParser parseType oParenT cParenT commaT
(BracketType Parens)
<|> braces parseType (BracketType Braces)
<|> brackets typeOrId (BracketType Squares)
lazyType = do q <- quMarkT
t <- primType
return (LazyType t (tokPos q))
<|> primType
mixType = do ts <- many1 lazyType
let t = if length ts == 1 then head ts else MixfixType ts
in kindAnno t
<|> return t
prodType = do (ts, ps) <- mixType `separatedBy` crossT
return (if length ts == 1 then head ts
else ProductType ts (map tokPos ps))
funType = do (ts, as) <- prodType `separatedBy` arrowT
return (makeFun ts as)
where makeFun [t] [] = t
makeFun [t,r] [a] = FunType t (fst a) r [snd a]
makeFun (t:r) (a:b) = makeFun [t, makeFun r b] [a]
makeFun _ _ = error "makeFun got illegal argument"
arrowT = do a <- noQuMark funS
return (FunArr, tokPos a)
<|>
do a <- asKey pFun
return (PFunArr, tokPos a)
<|>
do a <- noQuMark contFun
return (ContFunArr, tokPos a)
<|>
do a <- asKey pContFun
return (PContFunArr, tokPos a)
parseType :: GenParser Char st Type
parseType = funType
-----------------------------------------------------------------------------
-- var decls, typevar decls, genVarDecls
-----------------------------------------------------------------------------
varDecls :: GenParser Char st [VarDecl]
varDecls = do (vs, ps) <- var `separatedBy` commaT
varDeclType vs ps
varDeclType vs ps = do c <- colonT
t <- parseType
return (makeVarDecls vs ps t (tokPos c))
makeVarDecls vs ps t q = zipWith (\ v p -> VarDecl v t Comma (tokPos p))
(init vs) ps ++ [VarDecl (last vs) t Other q]
varDeclDownSet vs ps =
do l <- lessT
t <- parseType
return (makeTypeVarDecls vs ps (Downset t) (tokPos l))
typeVarDecls :: GenParser Char st [TypeVarDecl]
typeVarDecls = do (vs, ps) <- typeVar `separatedBy` commaT
do c <- colonT
t <- parseClass
return (makeTypeVarDecls vs ps t (tokPos c))
<|> varDeclDownSet vs ps
<|> return (makeTypeVarDecls vs ps
(Universe nullPos) nullPos)
makeTypeVarDecls vs ps cl q = zipWith (\ v p ->
TypeVarDecl v cl Comma (tokPos p))
(init vs) ps
++ [TypeVarDecl (last vs) cl Other q]
isSimpleId (Id ts _ _) = null (tail ts) && head (tokStr (head ts))
`elem` caslLetters
idToToken (Id ts _ _) = head ts
genVarDecls = do (vs, ps) <- var `separatedBy` commaT
if all isSimpleId vs then
fmap (map GenVarDecl) (varDeclType vs ps)
<|> fmap (map GenTypeVarDecl)
(varDeclDownSet (map idToToken vs) ps)
else
fmap (map GenVarDecl) (varDeclType vs ps)
-----------------------------------------------------------------------------
-- typeArgs
-----------------------------------------------------------------------------
extTypeVar :: GenParser Char st (TypeVar, Variance, Pos)
extTypeVar = do t <- typeVar
do a <- plusT
return (t, CoVar, tokPos a)
<|>
do a <- plusT
return (t, ContraVar, tokPos a)
<|> return (t, InVar, nullPos)
isInVar(_, InVar, _) = True
isInVar(_,_,_) = False
typeArgs :: GenParser Char st [TypeArg]
typeArgs = do (ts, ps) <- extTypeVar `separatedBy` commaT
do c <- colonT
if all isInVar ts then
do k <- extClass
return (makeTypeArgs ts ps (tokPos c) k)
else do k <- parseClass
return (makeTypeArgs ts ps (tokPos c)
(ExtClass k InVar nullPos))
<|>
do l <- lessT
t <- parseType
return (makeTypeArgs ts ps (tokPos l)
(ExtClass (Downset t) InVar nullPos))
<|> return (makeTypeArgs ts ps nullPos
(ExtClass (Universe nullPos) InVar nullPos))
where mergeVariance k e (t, InVar, _) p =
TypeArg t e k p
mergeVariance k (ExtClass c _ _) (t, v, ps) p =
TypeArg t (ExtClass c v ps) k p
makeTypeArgs ts ps q e =
zipWith (mergeVariance Comma e) (init ts)
(map tokPos ps)
++ [mergeVariance Other e (last ts) q]
-----------------------------------------------------------------------------
-- type pattern
-----------------------------------------------------------------------------
typePatternToken :: GenParser Char st TypePattern
typePatternToken = fmap TypePatternToken (pToken (scanWords <|> placeS <|>
reserved (hascasl_type_ops ++
formula_ops ++
hascasl_reserved_ops)
scanAnySigns))
primTypePatternOrId = fmap TypePatternToken (idToken True)
<|> braces typePatternOrId (BracketTypePattern Braces)
<|> brackets typePatternOrId (BracketTypePattern Squares)
<|> bracketParser typePatternArgs oParenT cParenT semiT
(BracketTypePattern Parens)
typePatternOrId = do ts <- many1 primTypePatternOrId
return( if length ts == 1 then head ts
else MixfixTypePattern ts)
typePatternArgs = fmap TypePatternArgs typeArgs
primTypePattern = typePatternToken
<|> bracketParser typePatternArgs oParenT cParenT semiT
(BracketTypePattern Parens)
<|> braces typePattern (BracketTypePattern Braces)
<|> brackets typePatternOrId (BracketTypePattern Squares)
typePattern = do ts <- many1 primTypePattern
let t = if length ts == 1 then head ts
else MixfixTypePattern ts
in return t
-----------------------------------------------------------------------------
-- pattern
-----------------------------------------------------------------------------
-- a parsed pattern may also be interpreted as a type (by the mixfix analysis)
-- thus [ ... ] may be a mixfix-pattern, a compound list,
-- or an instantiation with types
-- special pattern needed that don't contain "->" at the top-level
-- because "->" should be recognized in case-expressions
-- flag b allows "->" in patterns
tokenPattern b = fmap PatternToken (idToken b)
primPattern b = tokenPattern b
<|> braces pattern (BracketPattern Braces)
<|> brackets pattern (BracketPattern Squares)
<|> bracketParser patterns oParenT cParenT semiT
(BracketPattern Parens)
patterns = do (ts, ps) <- pattern `separatedBy` commaT
let tp = if length ts == 1 then head ts
else TuplePattern ts (map tokPos ps)
in return tp
mixPattern b =
do l <- many1 $ primPattern b
let p = if length l == 1 then head l else MixfixPattern l
in typedPattern p <|> return p
typedPattern p = do { c <- colonT
; t <- parseType
; return (TypedPattern p t [tokPos c])
}
asPattern b =
do v <- mixPattern b
do c <- asT
t <- mixPattern b
return (AsPattern v t [tokPos c])
<|> return v
-- True allows "->" in patterns
pattern = asPattern True
-----------------------------------------------------------------------------
-- instOpName
-----------------------------------------------------------------------------
-- places may follow instantiation lists
instOpName = do i@(Id is cs ps) <- uninstOpName
if isPlace (last is) then return (InstOpName i [])
else do l <- many (brackets parseType Types)
u <- many placeT
return (InstOpName (Id (is++u) cs ps) l)
-----------------------------------------------------------------------------
-- typeScheme
-----------------------------------------------------------------------------
typeScheme = do f <- forallT
(ts, cs) <- typeVarDecls `separatedBy` semiT
d <- dotT
t <- typeScheme
return (TypeScheme (concat ts) t (toPos f cs d))
<|> fmap SimpleTypeScheme parseType
-----------------------------------------------------------------------------
-- term
-----------------------------------------------------------------------------
tToken = pToken(scanFloat <|> scanString
<|> scanQuotedChar <|> scanDotWords <|> scanTermWords
<|> reserved hascasl_reserved_ops scanAnySigns
<|> placeS <?> "id/literal" )
termToken = fmap TermToken (asKey exEqual <|> tToken)
-- flag if within brackets: True allows "in"-Terms
primTerm b = termToken
<|> braces term (BracketTerm Braces)
<|> brackets term (BracketTerm Squares)
<|> parenTerm
<|> forallTerm b
<|> exTerm b
<|> lambdaTerm b
<|> caseTerm b
<|> letTerm b
parenTerm = do o <- oParenT
varTerm o
<|>
qualOpName o
<|>
qualPredName o
<|>
do (ts, ps) <- option ([],[]) (term `separatedBy` commaT)
p <- cParenT
return (BracketTerm Parens ts (toPos o ps p))
partialTypeScheme :: GenParser Char st (Token, TypeScheme)
partialTypeScheme = do q <- qColonT
t <- parseType
return (q, SimpleTypeScheme
(FunType (TupleType [] [tokPos q])
PFunArr t [tokPos q]))
<|> bind (,) colonT typeScheme
varTerm o = do v <- asKey varS
i <- var
c <- colonT
t <- parseType
p <- cParenT
return (QualVar i t (toPos o [v, c] p))
qualOpName o = do { v <- asKey opS
; i <- instOpName
; (c, t) <- partialTypeScheme
; p <- cParenT
; return (QualOp i t (toPos o [v, c] p))
}
predType t = FunType t PFunArr (ProductType [] []) []
predTypeScheme (SimpleTypeScheme t) = SimpleTypeScheme (predType t)
predTypeScheme (TypeScheme vs t ps) = TypeScheme vs (predTypeScheme t) ps
qualPredName o = do { v <- asKey predS
; i <- instOpName
; c <- colonT
; t <- typeScheme
; p <- cParenT
; return (QualOp i (predTypeScheme t)
(toPos o [v, c] p))
}
typeQual b =
do q <- colonT
return (OfType, q)
<|>
if b then
do q <- asKey asS
return (AsType, q)
<|>
do q <- asKey inS
return (InType, q)
else
do q <- asKey asS
return (AsType, q)
typedTerm f b =
do (q, p) <- typeQual b
t <- parseType
return (TypedTerm f q t (tokPos p))
mixTerm b =
do ts <- many1 $ primTerm b
let t = if length ts == 1 then head ts else MixfixTerm ts
in typedTerm t b <|> return t
term = mixTerm True
-----------------------------------------------------------------------------
-- quantified term
-----------------------------------------------------------------------------
forallTerm b =
do f <- forallT
(vs, ps) <- genVarDecls `separatedBy` semiT
d <- dotT
t <- mixTerm b
return (QuantifiedTerm Universal (concat vs) t
(toPos f ps d))
exQuant =
do { q <- asKey (existsS++exMark)
; return (Unique, q)
}
<|>
do { q <- asKey existsS
; return (Existential, q)
}
exTerm b =
do { (q, p) <- exQuant
; (vs, ps) <- varDecls `separatedBy` semiT
; d <- dotT
; f <- mixTerm b
; return (QuantifiedTerm q (map GenVarDecl (concat vs)) f
(toPos p ps d))
}
lamDot = do d <- asKey (dotS++exMark) <|> asKey (cDot++exMark)
return (Total,d)
<|>
do d <- dotT
return (Partial,d)
lambdaTerm b =
do l <- asKey lamS
pl <- lamPattern
(k, d) <- lamDot
t <- mixTerm b
return (LambdaTerm pl k t (toPos l [] d))
lamPattern = do (vs, ps) <- varDecls `separatedBy` semiT
return [PatternVars (concat vs) (map tokPos ps)]
<|>
many (bracketParser patterns oParenT cParenT semiT
(BracketPattern Parens))
-----------------------------------------------------------------------------
-- case-term
-----------------------------------------------------------------------------
-- b1 allows "->", b2 allows "in"-Terms
patternTermPair :: Bool -> Bool -> String -> GenParser Char st ProgEq
patternTermPair b1 b2 sep =
do p <- asPattern b1
s <- asKey sep
t <- mixTerm b2
return (ProgEq p t (tokPos s))
caseTerm b =
do c <- asKey caseS
t <- term
o <- asKey ofS
(ts, ps) <- patternTermPair False b funS `separatedBy` barT
return (CaseTerm t ts (map tokPos (c:o:ps)))
-----------------------------------------------------------------------------
-- annos and lookahead after ";"
-----------------------------------------------------------------------------
-- skip to leading annotation and read many
annos :: GenParser Char st [Annotation]
annos = skip >> many (annotationL << skip)
tryItemEnd :: [String] -> GenParser Char st ()
tryItemEnd l =
try (do { c <- lookAhead (annos >>
(single (oneOf "\"([{")
<|> placeS
<|> scanAnySigns
<|> many scanLPD))
; if null c || c `elem` l then return () else unexpected c
})
-- "axiom/axioms ... ; exists ... " is not supported
startKeyword = dotS:cDot: hascasl_reserved_words
-----------------------------------------------------------------------------
-- let-term
-----------------------------------------------------------------------------
letTerm b =
do l <- asKey letS
(es, ps) <- patternTermPair True False equalS `separatedBy` semiT
i <- asKey inS
t <- mixTerm b
return (LetTerm es t (toPos l ps i))