{- |

Module : $Header$

Description : signatures with symbol sets

Copyright : (c) DFKI GmbH, Uni Bremen 2002-2007

License : similar to LGPL, see HetCATS/LICENSE.txt or LIZENZ.txt

Maintainer : Christian.Maeder@dfki.de

Stability : provisional

Portability : portable

Some functions that operate over signatures need to be extended to work over

signatures with symbol sets for every logic

-}

module Common.ExtSign where

import qualified Data.Set as Set

import Common.Doc

import Common.DocUtils

-- | signatures with symbol sets.

-- (The Ord instance is needed for the ATC generation)

data Ord symbol => ExtSign sign symbol = ExtSign

{ plainSign :: sign

, nonImportedSymbols :: (Set.Set symbol)

} deriving Show

instance (Ord symbol, Ord sign) => Eq (ExtSign sign symbol) where

a == b = compare a b == EQ

instance (Ord symbol, Ord sign) => Ord (ExtSign sign symbol) where

compare (ExtSign s1 _) (ExtSign s2 _) = compare s1 s2

instance (Pretty sign, Ord symbol, Pretty symbol)

=> Pretty (ExtSign sign symbol) where

pretty (ExtSign s sys) =

sep [pretty s, if Set.null sys then empty else pretty sys]

mkExtSign :: Ord symbol => sign -> ExtSign sign symbol

mkExtSign s = ExtSign s Set.empty