{- |

Module : $Header$

Description : Parser for basic specs

Copyright : (c) Dominik Dietrich, DFKI Bremen 2010

License : GPLv2 or higher, see LICENSE.txt

Maintainer : dominik.dietrich@dfki.de

Stability : experimental

Portability : portable

Parser for abstract syntax for CSL

-}

module CSL.Parse_AS_Basic where

import qualified Common.AnnoState as AnnoState

import Common.Id as Id

import Common.Keywords as Keywords

import Common.Lexer as Lexer

import Common.Parsec

import Common.AS_Annotation as AS_Anno

import CSL.AS_BASIC_CSL

import CSL.Keywords

import Text.ParserCombinators.Parsec as Parsec

import Control.Monad

-- the basic lexer, test using e.g. runParser identifier 0 "" "asda2_3"

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

-- * Interface to the syntax class

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

parseBasicSpec :: Maybe (AnnoState.AParser st BASIC_SPEC)

parseBasicSpec = Just basicSpec

parseSymbItems :: Maybe (GenParser Char st SYMB_ITEMS)

parseSymbItems = Just symbItems

parseSymbMapItems :: Maybe (GenParser Char st SYMB_MAP_ITEMS)

parseSymbMapItems = Just symbMapItems

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

-- * Parser utils

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

parseError :: String -> CharParser st a

parseError s = do

p <- getPosition

return $ error

$ concat [ "Parse error at line: ", show (Parsec.sourceLine p)

, " col: ", show (Parsec.sourceColumn p), "\n", s]

pComma :: CharParser st String

pComma = lexemeParser $ Lexer.keySign $ string ","

pSemi :: CharParser st String

pSemi = lexemeParser $ Lexer.keySign $ string ";"

lstring :: String -> CharParser st String

lstring = lexemeParser . string

-- | parser for symbols followed by whitechars

lexemeParser :: CharParser st a -> CharParser st a

lexemeParser = (<< skip)

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

-- * Parser for Expressions

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

{- | parsing of identifiers. an identifier is a letter followed by

letters, numbers, or _, but not a keyword -}

identifier :: CharParser st Id.Token

identifier =

lexemeParser $ Lexer.pToken $ reserved allKeywords Lexer.scanAnyWords

prefixidentifier :: CharParser st Id.Token

prefixidentifier =

lexemeParser $ Lexer.pToken $ Lexer.scanAnySigns <|> Lexer.scanAnyWords

-- | parses a possibly signed number to an EXPRESSION

signednumberExp :: CharParser st EXPRESSION

signednumberExp =

let f (eN, rg) = either (flip Int rg) (flip Double rg) eN

in signednumber >-> f

-- | parses a possibly signed number (both integers and floats)

signednumber :: CharParser st (Either APInt APFloat, Range)

signednumber =

let f c x = return (c $ read $ tokStr x, tokPos x)

g x | isFloating x = f Right x

| otherwise = f Left x

in Lexer.pToken Lexer.scanFloatExt >>= g

oneOfKeys :: [String] -> CharParser st String

oneOfKeys l = lexemeParser $ Lexer.keySign $ choice $ map tryString l

expression :: CharParser st EXPRESSION

expression = do

exp1 <- factor

exps <- many $ pair (oneOfKeys ["+", "-"]) factor

return $ if null exps then exp1

else foldr (\ a b -> mkOp (fst a) [b, snd a]) exp1 exps

-- | parse a product of basic expressions

factor :: CharParser st EXPRESSION

factor = do

exp1 <- expexp

exps <- many

$ pair (oneOfKeys ["*", "/"]) factor

if null exps then return exp1

else return $ foldr (\ a b -> mkOp (fst a) [b, snd a]) exp1 exps

-- | parse a sequence of exponentiations

expexp :: CharParser st EXPRESSION

expexp = do

exp1 <- expatom

exps <- many

$ pair (oneOfKeys ["**", "^"]) expexp

if null exps then return exp1

else return $ foldr (\ a b -> mkOp (fst a) [b, snd a]) exp1 exps

-- | parse a basic expression

expatom :: CharParser st EXPRESSION

expatom = try signednumberExp <|> (oParenT >> expression << cParenT)

<|> listexp <|> intervalexp <|> expsymbol

expsymbol :: CharParser st EXPRESSION

expsymbol =

do

ident <- prefixidentifier -- EXTENDED

ep <- option ([],[])

$ oBracketT >> Lexer.separatedBy extparam pComma << cBracketT

exps <- option ([],[])

$ oParenT >> Lexer.separatedBy formulaorexpression pComma

<< cParenT

return $ Op (tokStr ident) (fst ep) (fst exps) nullRange

-- | parses a list expression

listexp :: CharParser st EXPRESSION

listexp = do

Lexer.keySign $ string "{"

elems <- Lexer.separatedBy formulaorexpression pComma

Lexer.keySign $ string "}"

return (List (fst elems) nullRange)

intervalexp :: CharParser st EXPRESSION

intervalexp = do

nums <- lstring "[" >> Lexer.separatedBy signednumber pComma << lstring "]"

let getFloat = either fromInteger id

case fst nums of

[(x, rg1), (y, rg2)] -> return $ Interval (getFloat x) (getFloat y) $ Range

$ joinRanges $ map rangeToList [rg1, rg2]

_ -> parseError

"intervalexp: Parse error: interval with other than two arguments"

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

-- ** parser for extended parameter, e.g., [I=0,...]

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

extparam :: CharParser st EXTPARAM

extparam = do

i <- identifier

liftM2 (EP i) (oneOfKeys ["=", "<=", ">=", "!=", "<", ">", "-|"])

$ option 0 $ signednumber

>-> either id (error "extparam: floats not supported") . fst

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

-- * parser for formulas

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

parseVarList :: CharParser st EXPRESSION

parseVarList = do

Lexer.keySign (string "{")

elems <- Lexer.separatedBy parseVar pComma

Lexer.keySign (string "}")

return (List (fst elems) nullRange)

parseVar :: CharParser st EXPRESSION

parseVar = do

ident <- identifier

return (Var ident)

quantFormula :: String -> CharParser st EXPRESSION

quantFormula q = do

Lexer.keySign (string q)

oParenT

vars <- ( parseVar <|> parseVarList)

pComma

expr <- formulaorexpression

cParenT

return (mkOp q [vars, expr])

-- | parser for atoms

truefalseFormula :: CharParser st EXPRESSION

truefalseFormula =

do

lexemeParser (Lexer.keyWord (tryString "true"))

return (mkOp "True" [])

<|>

do

lexemeParser (Lexer.keyWord (tryString "false"))

return (mkOp "False" [])

<|> quantFormula "ex" <|> quantFormula "all"

-- | parser for predicates

predFormula :: CharParser st EXPRESSION

predFormula = do

exp1 <- expression

mExp2 <- optionMaybe

$ pair (oneOfKeys ["<=", ">=", "!="]

<|> lexemeParser (single $ oneOf "=<>")) expression

case mExp2 of

Just (op, exp2) -> return $ mkOp op [exp1, exp2]

_ -> return $ exp1

atomicFormula :: CharParser st EXPRESSION

atomicFormula = truefalseFormula <|> predFormula <|> parenFormula

-- | parser for formulas

aFormula :: CharParser st EXPRESSION

aFormula = try negFormula <|> impOrFormula

negFormula :: CharParser st EXPRESSION

negFormula = do

lexemeParser (Lexer.keyWord (tryString "not"))

f <- atomicFormula

return (mkOp "not" [f])

-- | parses a formula within brackets

parenFormula :: CharParser st EXPRESSION

parenFormula = do

lexemeParser oParenT

f <- aFormula

lexemeParser cParenT

return f

-- | parser for implications and ors (same precedence)

impOrFormula :: CharParser st EXPRESSION

impOrFormula = do

f1 <- andFormula

opfs <- many $ pair (lexemeParser $ Lexer.keyWord

$ tryString "or" <|> tryString "impl") impOrFormula

if null opfs then return f1

else return $ foldr (\ (a1, a2) b -> mkOp (case a1 of

"or" -> "or"

"impl" -> "impl"

_ -> error "impl or or expected")

[b, a2]

) f1 opfs

-- | a parser for and sequence of and formulas

andFormula :: CharParser st EXPRESSION

andFormula = do

f1 <- atomicFormula

opfs <- many $ pair (lexemeParser $ keyWord $ tryString "and") atomicFormula

if null opfs then return f1

else return $ foldr (\ a b -> (mkOp "and" [b, snd a])) f1 opfs

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

-- * Parser for Commands

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

formulaorexpression :: CharParser st EXPRESSION

formulaorexpression = try aFormula <|> expression

-- | parser for commands

command :: CharParser (AnnoState.AnnoState st) CMD

command = reduceCommand <|> try assignment <|> repeatExpr <|> caseExpr

<|> constraint

reduceCommand :: CharParser st CMD

reduceCommand = do

cmd <- lexemeParser $ Lexer.keyWord $ choice $ map tryString

["solve", "simplify", "divide", "int", "rlqe", "factorize"]

oParenT

arg1 <- formulaorexpression

args <- many $ pComma >> formulaorexpression

cParenT

return $ Cmd cmd $ arg1 : args

assignment :: CharParser st CMD

assignment = do

ident <- expsymbol

lexemeParser $ tryString ":="

exp' <- expression

return $ Cmd ":=" [ident, exp']

constraint :: CharParser st CMD

constraint = do

exp' <- try aFormula

case exp' of

Op _ _ _ _ ->

return $ Cmd "constraint" [exp']

_ -> fail "Malformed constraint"

repeatExpr :: CharParser (AnnoState.AnnoState st) CMD

repeatExpr = do

lstring "repeat"

statements <- many1 (AnnoState.dotT >> AnnoState.allAnnoParser command)

lstring "until"

cstr <- aFormula

return $ Repeat cstr $ map AS_Anno.item statements

singleCase :: CharParser (AnnoState.AnnoState st) (EXPRESSION, [CMD])

singleCase = do

lstring "case"

cond <- aFormula

lstring ":"

statements <- many1 (AnnoState.dotT >> AnnoState.allAnnoParser command)

return (cond, map AS_Anno.item statements)

caseExpr :: CharParser (AnnoState.AnnoState st) CMD

caseExpr = many1 singleCase >-> Cond << lstring "end"

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

-- * parser spec entries

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

-- | parser for operator declarations: example: operator a,b,c

opItem :: CharParser st OP_ITEM

opItem = do

Lexer.keySign (lexemeParser (tryString "operator"))

vars <- sepBy1 identifier pComma

return $ Op_item vars nullRange

-- | Parser for variable declarations: example: vars x,y in {1,2}; z in [-1,1]

varItems :: CharParser st [VAR_ITEM]

varItems = oneOfKeys ["vars", "var"] >> sepBy1 varItem pSemi

-- | Parser for a variable declaration: example: vars x,y in {1,2}

varItem :: CharParser st VAR_ITEM

varItem = do

vars <- sepBy1 identifier pComma

oneOfKeys ["in"]

dom <- parseDomain

return $ Var_item vars dom nullRange

parseDomain :: CharParser st Domain

parseDomain = do

lp <- lexemeParser $ oneOf "{[]"

gcl <- sepBy1 (signednumber >-> either GCI GCR . fst) pComma

rp <- lexemeParser $ oneOf "[]}"

let f o c = case gcl of

[lb, rb] -> return $ IntVal (lb, o) (rb, c)

_ -> parseError "parseDomain: incorrect interval-list"

case [lp, rp] of

"{}" -> return $ Set gcl

"[]" -> f True True

"[[" -> f True False

"][" -> f False False

"]]" -> f False True

_ -> parseError "parseDomain: malformed domain parens"

-- | Toplevel parser for basic specs

basicSpec :: AnnoState.AParser st BASIC_SPEC

basicSpec =

AnnoState.annosParser parseBasicItems >-> Basic_spec

<|> (Lexer.oBraceT >> Lexer.cBraceT >> return (Basic_spec []))

-- | Parser for basic items

parseBasicItems :: AnnoState.AParser st BASIC_ITEMS

parseBasicItems = parseOpDecl <|> parseVarDecl <|> parseAxItems

-- | parser for predicate declarations

parseOpDecl :: AnnoState.AParser st BASIC_ITEMS

parseOpDecl = opItem >-> Op_decl

-- | parser for predicate declarations

parseVarDecl :: AnnoState.AParser st BASIC_ITEMS

parseVarDecl = varItems >-> Var_decls

-- | parser for Axiom_item

parseAxItems :: AnnoState.AParser st BASIC_ITEMS

parseAxItems = do

AnnoState.dotT

cmd <- (AnnoState.allAnnoParser command)

return $ Axiom_item cmd

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

-- * parser for symbol maps etc.

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

-- | parsing a prop symbol

symb :: GenParser Char st SYMB

symb = identifier >-> Symb_id

-- | parsing one symbol or a mapping of one to a second symbol

symbMap :: GenParser Char st SYMB_OR_MAP

symbMap = do

s <- symb

do f <- pToken $ toKey mapsTo

t <- symb

return (Symb_map s t $ tokPos f)

<|> return (Symb s)

-- | Parse a list of comma separated symbols.

symbItems :: GenParser Char st SYMB_ITEMS

symbItems = do

(is, ps) <- symbs

return (Symb_items is $ catRange ps)

-- | parse a comma separated list of symbols

symbs :: GenParser Char st ([SYMB], [Token])

symbs = do

s <- symb

do c <- commaT `followedWith` symb

(is, ps) <- symbs

return (s : is, c : ps)

<|> return ([s], [])

-- | parse a list of symbol mappings

symbMapItems :: GenParser Char st SYMB_MAP_ITEMS

symbMapItems = do

(is, ps) <- symbMaps

return (Symb_map_items is $ catRange ps)

-- | parse a comma separated list of symbol mappings

symbMaps :: GenParser Char st ([SYMB_OR_MAP], [Token])

symbMaps = do

s <- symbMap

do c <- commaT `followedWith` symb

(is, ps) <- symbMaps

return (s : is, c : ps)

<|> return ([s], [])

parseResult :: String -> Maybe EXPRESSION

parseResult inp = case runParser formulaorexpression "" "" inp of

Left _ -> Nothing

Right s -> Just s