{- |

Module : ./CASL/SymbolParser.hs

Description : Parser for symbols in translations and reductions

Copyright : (c) Christian Maeder, Uni Bremen 2002-2006

License : GPLv2 or higher, see LICENSE.txt

Maintainer : Christian.Maeder@dfki.de

Stability : provisional

Portability : portable

Parsing symbols for translations and reductions

-}

module CASL.SymbolParser

( symbItems

, symbItem

, symbMapItems

, opOrPredType

, symbKind

) where

import CASL.AS_Basic_CASL

import CASL.Formula

import CASL.ToDoc ()

import Common.AnnoState

import Common.DocUtils

import Common.Id

import Common.Keywords

import Common.Lexer

import Common.Token

import Text.ParserCombinators.Parsec

-- | parsing a possibly qualified identifier

symb :: [String] -> SYMB_KIND -> AParser st SYMB

symb ks k = parseId ks >>= \ i -> case k of

Sorts_kind -> return $ Symb_id i

_ -> case k of

Ops_kind -> do

c <- colonST

o <- opType ks

return $ Qual_id i (O_type o) $ tokPos c

Preds_kind -> do

c <- colonT

p <- predType ks

return $ Qual_id i (P_type p) $ tokPos c

_ -> do

c <- colonST

t <- opOrPredType ks

return (Qual_id i t $ tokPos c)

<|> return (Symb_id i)

-- | parsing a type for an operation or a predicate

opOrPredType :: [String] -> AParser st TYPE

opOrPredType ks =

do (b, s, p) <- opSort ks

if b then return (O_type (Op_type Partial [] s p))

else do

c <- crossT

(ts, ps) <- sortId ks `separatedBy` crossT

fmap O_type (opFunSort ks (s : ts) (c : ps))

<|> return (P_type $ Pred_type (s : ts) $ catRange $ c : ps)

<|> fmap O_type (opFunSort ks [s] [])

<|> return (A_type s)

<|> fmap P_type predUnitType

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

symbMap :: [String] -> SYMB_KIND -> AParser st SYMB_OR_MAP

symbMap ks k =

do s <- symb ks k

do

f <- asKey mapsTo

k2 <- option Implicit $ fmap fst symbKind

case joinSymbKinds k k2 of

Nothing -> fail $ "contradicting symbol kinds '"

++ showDoc k "' and '" ++ showDoc k2 "'"

Just k3 -> do

t <- symb ks k3

return (Symb_map s t $ tokPos f)

<|> return (Symb s)

joinSymbKinds :: SYMB_KIND -> SYMB_KIND -> Maybe SYMB_KIND

joinSymbKinds k1 k2 = case k1 of

Implicit -> Just k2

_ -> if k2 == Implicit || k1 == k2 then Just k1 else Nothing

-- | parse a kind keyword

symbKind :: AParser st (SYMB_KIND, Token)

symbKind =

choice (map (\ (v, s) -> do

q <- pluralKeyword s

return (v, q))

[(Sorts_kind, sortS), (Ops_kind, opS), (Preds_kind, predS)])

<?> "kind"

{- | Parse a possible kinded list of comma separated CASL symbols.

The argument is a list of keywords to avoid as identifiers. -}

symbItems :: [String] -> AParser st SYMB_ITEMS

symbItems ks =

do (is, ps) <- symbs ks Implicit

return (Symb_items Implicit is $ catRange ps)

<|>

do (k, p) <- symbKind

(is, ps) <- symbs ks k

return (Symb_items k is $ catRange $ p : ps)

-- | Parse a possible kinded CASL symbol.

symbItem :: [String] -> AParser st SYMB_ITEMS

symbItem ks = do

i <- symb ks Implicit

return $ Symb_items Implicit [i] $ getRange i

<|> do

(k, p) <- symbKind

i <- symb ks k

return $ Symb_items k [i] $ catRange [p]

-- | parse a comma separated list of symbols

symbs :: [String] -> SYMB_KIND -> AParser st ([SYMB], [Token])

symbs ks k =

do s <- symb ks k

do

c <- commaT `followedWith` parseId ks

(is, ps) <- symbs ks k

return (s : is, c : ps)

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

-- | parse a possible kinded list of CASL symbol mappings

symbMapItems :: [String] -> AParser st SYMB_MAP_ITEMS

symbMapItems ks =

do (is, ps) <- symbMaps ks Implicit

return (Symb_map_items Implicit is $ catRange ps)

<|>

do (k, p) <- symbKind

(is, ps) <- symbMaps ks k

return (Symb_map_items k is $ catRange $ p : ps)

-- | parse a comma separated list of symbol mappings

symbMaps :: [String] -> SYMB_KIND -> AParser st ([SYMB_OR_MAP], [Token])

symbMaps ks k =

do s <- symbMap ks k

do

c <- commaT `followedWith` parseId ks

(is, ps) <- symbMaps ks k

return (s : is, c : ps)

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