{- HetCATS/HasCASL/ParseTerm.hs

$Id$

Authors: Christian Maeder

Year: 2002

parser for HasCASL kind, types, terms and pattern/equations

-}

module ParseTerm where

import Id

import Keywords

import Lexer

import HToken

import As

import Parsec

import AS_Annotation

import Anno_Parser(annotationL)

colonT = asKey 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

-----------------------------------------------------------------------------

parseClass = do t <- asKey typeS

return (Universe (tokPos t))

<|>

fmap ClassName className

<|>

do o <- oParenT

(cs, ps) <- parseClass `separatedBy` commaT

c <- cParenT

return (Intersection cs (map tokPos (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)

idToken = pToken (scanQuotedChar <|> scanDotWords

<|> scanDigit <|> scanWords <|> placeS <|>

reserved (formula_ops ++ hascasl_reserved_ops) scanAnySigns)

typeToken :: GenParser Char st Type

typeToken = fmap TypeToken (pToken (toKey typeS <|> scanWords <|> placeS <|>

reserved (hascasl_type_ops ++

formula_ops ++

hascasl_reserved_ops)

scanAnySigns))

braces p c = bracketParser p oBraceT cBraceT commaT c

primTypeOrId = fmap TypeToken idToken

<|> 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]

arrowT = do a <- try(asKey funS)

return (FunArr, tokPos a)

<|>

do a <- try(asKey pFun)

return (PFunArr, tokPos a)

<|>

do a <- try(asKey contFun)

return (ContFunArr, tokPos a)

<|>

do a <- try(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

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]

typeVarDecls :: GenParser Char st [TypeVarDecl]

typeVarDecls = do (vs, ps) <- typeVar `separatedBy` commaT

do c <- colonT

t <- parseClass

return (makeTypeVarDecls vs ps t (tokPos c))

<|>

do l <- lessT

t <- parseType

return (makeTypeVarDecls vs ps (Downset t) (tokPos l))

<|> 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

do c <- colonT

t <- parseType

return (map GenVarDecl

(makeVarDecls vs ps t (tokPos c)))

<|>

do l <- lessT

t <- parseType

return (map GenTypeVarDecl

(makeTypeVarDecls

(map idToToken vs) ps

(Downset t) (tokPos l)))

<|> return(map GenTypeVarDecl

(makeTypeVarDecls

(map idToToken vs) ps

(Universe nullPos) nullPos))

else

do c <- colonT

t <- parseType

return (map GenVarDecl

(makeVarDecls vs ps t (tokPos c)))

-----------------------------------------------------------------------------

-- 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

<|> 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

tokenPattern = fmap PatternToken idToken

primPattern = tokenPattern

<|> 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 = do l <- many1 primPattern

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 = do { v <- mixPattern

; do { c <- asT

; t <- mixPattern

; return (AsPattern v t [tokPos c])

}

<|> return v

}

pattern = asPattern

-----------------------------------------------------------------------------

-- 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 (map tokPos (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 (try (asKey exEqual) <|> tToken)

primTerm = termToken

<|> braces term (BracketTerm Braces)

<|> brackets term

(BracketTerm Squares)

<|> parenTerm

<|> forallTerm

<|> exTerm

<|> lambdaTerm

<|> caseTerm

parenTerm = do o <- oParenT

varTerm o

<|>

qualOpName o

<|>

qualPredName o

<|>

do (ts, ps) <- option ([],[]) (term `separatedBy` commaT)

p <- cParenT

return (BracketTerm Parens ts (map tokPos (o:ps++[p])))

partialTypeScheme :: GenParser Char st (Token, TypeScheme)

partialTypeScheme = do q <- try (qColonT)

t <- parseType

return (q, SimpleTypeScheme (LazyType t (tokPos q)))

<|> bind (,) colonT typeScheme

varTerm o = do v <- asKey varS

i <- var

c <- colonT

t <- parseType

p <- cParenT

return (QualVar i t (map tokPos [o,v,c,p]))

qualOpName o = do { v <- asKey opS

; i <- instOpName

; (c, t) <- partialTypeScheme

; p <- cParenT

; return (QualOp i t (map tokPos [o,v,c,p]))

}

predType t = FunType t PFunArr (ProductType [] []) nullPos

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)

(map tokPos [o,v,c,p]))

}

typeQual = try $

do q <- colonT

return (OfType, q)

<|>

do q <- asKey (asS)

return (AsType, q)

<|>

do q <- asKey (inS)

return (InType, q)

typedTerm f = do (q, p) <- typeQual

t <- parseType

return (TypedTerm f q t (tokPos p))

mixTerm = do ts <- many1 primTerm

let t = if length ts == 1 then head ts else MixfixTerm ts

in typedTerm t <|> return t

term = do t <- mixTerm

whereTerm t <|> return t

-----------------------------------------------------------------------------

-- quantified term

-----------------------------------------------------------------------------

forallTerm = do f <- try forallT

(vs, ps) <- genVarDecls `separatedBy` semiT

d <- dotT

t <- term

return (QuantifiedTerm Universal (concat vs) t

(map tokPos (f:ps++[d])))

exQuant = try(

do { q <- asKey (existsS++exMark)

; return (Unique, q)

}

<|>

do { q <- asKey existsS

; return (Existential, q)

})

exTerm = do { (q, p) <- exQuant

; (vs, ps) <- varDecls `separatedBy` semiT

; d <- dotT

; f <- term

; return (QuantifiedTerm q (map GenVarDecl (concat vs)) f

(map tokPos (p:ps++[d])))

}

lamDot = do d <- asKey (dotS++exMark) <|> asKey (cDot++exMark)

return (Total,d)

<|>

do d <- dotT

return (Partial,d)

lambdaTerm = do l <- try (asKey lamS)

pl <- lamPattern

(k, d) <- lamDot

t <- term

return (LambdaTerm pl k t (map tokPos [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

-----------------------------------------------------------------------------

patternTermPair :: String -> GenParser Char st ProgEq

patternTermPair sep = do p <- pattern

s <- asKey sep

t <- term

return (ProgEq p t (tokPos s))

caseTerm = do c <- try(asKey caseS)

t <- term

o <- asKey ofS

(ts, ps) <- patternTermPair 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

-----------------------------------------------------------------------------

-- where-term

-----------------------------------------------------------------------------

whereEquations =

do { p <- patternTermPair equalS

; do { s <- semiT

; do { tryItemEnd startKeyword

; return ([p], [s])

}

<|>

do { (ps, ts) <- whereEquations

; return (p:ps, s:ts)

}

}

<|>

return ([p], [])

}

whereTerm t = do w <- try $ asKey whereS

(ts, ps) <- whereEquations

return (WhereTerm t ts (map tokPos (w:ps)))