{- |

Module : $Header$

Description : abstract syntax for Relational Schemes

Copyright : Dominik Luecke, Uni Bremen 2008

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

Maintainer : luecke@informatik.uni-bremen.de

Stability : provisional

Portability : portable

Abstract syntax for Relational Schemes

-}

module RelationalScheme.AS where

import Common.Id

import Common.AS_Annotation

import Common.Doc

import Common.DocUtils

import RelationalScheme.Keywords

import RelationalScheme.Sign

-- DrIFT command

{-! global: UpPos !-}

data RSRelType = RSone_to_one | RSone_to_many | RSmany_to_one | RSmany_to_many

deriving (Eq, Ord, Show)

-- first Id is TableId, second is columnId

data RSQualId = RSQualId Id Id Range

deriving (Eq, Ord, Show)

data RSRel = RSRel [RSQualId] [RSQualId] RSRelType Range

deriving (Eq, Ord, Show)

data RSRelationships = RSRelationships [Annoted RSRel] Range

deriving (Eq, Show)

data RSScheme = RSScheme RSTables RSRelationships Range

deriving (Eq, Show)

type Sentence = RSRel

instance Pretty RSScheme where

pretty = text . show

instance Pretty RSRel where

pretty = text . show