{-# OPTIONS -fno-warn-missing-methods #-}

{- HetCATS/Modal/Logic_Modal.hs

$Id$

Authors: Wiebke Herding

Year: 2003

-}

module Modal.Logic_Modal where

import Logic.Logic

import Common.Id

import Common.Lib.Map as Map

import Common.Lib.Set as Set

import Data.Maybe

import Modal.AS_Modal

data Modal = Modal deriving (Show)

instance Language Modal where -- default definition is okay

type Sign = Set Id

instance Show Sign where

type Morphism = (Sign, EndoMap Id, Sign)

instance Category Modal Sign Morphism

where

-- ide :: id -> object -> morphism

ide Modal sigma = (sigma, Map.fromList

[(i,i) | i<- Set.toList sigma], sigma)

-- comp :: id -> morphism -> morphism -> Maybe morphism

comp Modal (sigma1 ,m1,_) (_,m2,sigma2) =

Just (sigma1,Map.union m1 m2,sigma2)

-- dom, cod :: id -> morphism -> object

dom Modal (sigma,_,_) = sigma

cod Modal (_,_,sigma) = sigma

-- legal_obj :: id -> object -> Bool

legal_obj Modal _ = True

-- legal_mor :: id -> morphism -> Bool

legal_mor Modal (sigma,m,_)

| Map.keys m == Set.toList sigma = True

| True = False

-- abstract syntax, parsing (and printing)

-- instance Syntax Modal BASIC_SPEC

-- SYMB_ITEMS SYMB_MAP_ITEMS

-- where

-- parse_basic_spec :: id -> Maybe(ParseFun basic_spec)

-- parse_symb_items :: id -> Maybe(ParseFun symb_items)

-- parse_symb_map_items :: id -> Maybe(ParseFun symb_map_items)