{- |

Module : $Header$

Copyright : (c) Christian Maeder, Uni Bremen 2002-2004

Licence : similar to LGPL, see HetCATS/LICENCE.txt or LIZENZ.txt

Maintainer : maeder@tzi.de

Stability : provisional

Portability : portable

-}

{-

parse OP-ITEM and "op/ops OP-ITEM ; ... ; OP-ITEM"

parse PRED-ITEM and "op/ops PRED-ITEM ; ... ; PRED-ITEM"

http://www.cofi.info/Documents/CASL/Summary/

from 25 March 2001

C.2.1 Basic Specifications with Subsorts

-}

module CASL.OpItem (opItem, predItem) where

import Common.AnnoState

import Common.Id

import Common.Keywords

import Common.Lexer

import CASL.AS_Basic_CASL

import Common.AS_Annotation

import Text.ParserCombinators.Parsec

import Common.Token

import CASL.Formula

import Data.List(sort)

-- stupid cast

argDecl :: [String] -> AParser st ARG_DECL

argDecl = fmap (\(Var_decl vs s ps) -> Arg_decl vs s ps) . varDecl

-- non-empty

predHead :: [String] -> AParser st PRED_HEAD

predHead ks =

do o <- wrapAnnos oParenT

(vs, ps) <- argDecl ks `separatedBy` anSemi

p <- addAnnos >> cParenT

return $ Pred_head vs $ catPos (o:ps++[p])

opHead :: [String] -> AParser st OP_HEAD

opHead ks =

do Pred_head vs ps <- predHead ks

c <- anColon

(b, s, qs) <- opSort ks

return $ Op_head (if b then Partial else Total) vs s

(ps ++ tokPos c ++ qs)

opAttr :: AParsable f => [String] -> AParser st (OP_ATTR f, Token)

opAttr ks = do p <- asKey assocS

return (Assoc_op_attr, p)

<|>

do p <- asKey commS

return (Comm_op_attr, p)

<|>

do p <- asKey idemS

return (Idem_op_attr, p)

<|>

do p <- asKey unitS

t <- term ks

return (Unit_op_attr t, p)

isConstant :: OP_TYPE -> Bool

isConstant(Op_type _ [] _ _) = True

isConstant _ = False

toHead :: [Pos] -> OP_TYPE -> OP_HEAD

toHead c (Op_type k [] s ps) = Op_head k [] s (c ++ ps)

toHead _ _ = error "toHead got non-empty argument type"

opItem :: AParsable f => [String] -> AParser st (OP_ITEM f)

opItem ks =

do (os, cs) <- parseId ks `separatedBy` anComma

if isSingle os then

do c <- anColon

t <- opType ks

if isConstant t then

opBody ks (head os) (toHead (tokPos c) t)

<|> opAttrs ks os t [c] -- this always succeeds

else opAttrs ks os t [c]

<|>

do h <- opHead ks

opBody ks (head os) h

else

do c <- anColon

t <- opType ks

opAttrs ks os t (cs++[c])

opBody :: AParsable f => [String] -> OP_NAME -> OP_HEAD

-> AParser st (OP_ITEM f)

opBody ks o h =

do e <- equalT

a <- annos

t <- term ks

return $ Op_defn o h (Annoted t [] a []) $ tokPos e

opAttrs :: AParsable f => [String] -> [OP_NAME] -> OP_TYPE -> [Token]

-> AParser st (OP_ITEM f)

opAttrs ks os t c =

do q <- anComma

(as, cs) <- opAttr ks `separatedBy` anComma

let ps = sort (catPos (c ++ map snd as ++ (q:cs)))

return (Op_decl os t (map fst as) ps)

<|> return (Op_decl os t [] (catPos c))

-- overlap "o:t" DEF-or DECL "o:t=e" or "o:t, assoc"

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

-- predicates

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

predItem :: AParsable f => [String] -> AParser st (PRED_ITEM f)

predItem ks =

do (ps, cs) <- parseId ks `separatedBy` anComma

if isSingle ps then

predBody ks (head ps) (Pred_head [] [])

<|>

do h <- predHead ks

predBody ks (head ps) h

<|>

predTypeCont ks ps cs

else predTypeCont ks ps cs

predBody :: AParsable f => [String] -> PRED_NAME -> PRED_HEAD

-> AParser st (PRED_ITEM f)

predBody ks p h =

do e <- asKey equivS

a <- annos

f <- formula ks

return $ Pred_defn p h (Annoted f [] a []) $ tokPos e

predTypeCont :: [String] -> [PRED_NAME] -> [Token] -> AParser st (PRED_ITEM f)

predTypeCont ks ps cs =

do c <- colonT

t <- predType ks

return $ Pred_decl ps t $ catPos (cs++[c])