-- Created on: 1991-01-14
-- Created by: Arnaud BOUZY
-- Copyright (c) 1991-1999 Matra Datavision
-- Copyright (c) 1999-2012 OPEN CASCADE SAS
--
-- The content of this file is subject to the Open CASCADE Technology Public
-- License Version 6.5 (the "License"). You may not use the content of this file
-- except in compliance with the License. Please obtain a copy of the License
-- at http://www.opencascade.org and read it completely before using this file.
--
-- The Initial Developer of the Original Code is Open CASCADE S.A.S., having its
-- main offices at: 1, place des Freres Montgolfier, 78280 Guyancourt, France.
--
-- The Original Code and all software distributed under the License is
-- distributed on an "AS IS" basis, without warranty of any kind, and the
-- Initial Developer hereby disclaims all such warranties, including without
-- limitation, any warranties of merchantability, fitness for a particular
-- purpose or non-infringement. Please see the License for the specific terms
-- and conditions governing the rights and limitations under the License.


deferred class GeneralRelation from Expr
    
inherits TShared from MMgt 

    ---Purpose: Defines the general purposes of any relation between 
    --          expressions.

uses GeneralExpression from Expr,
    NamedUnknown from Expr,
    AsciiString from TCollection


raises OutOfRange from Standard,
    NumericError from Standard

is

    IsSatisfied(me)
    ---Purpose: Returns the current status of the relation
    ---Level: Advanced 
    returns Boolean
    is deferred;

    IsLinear(me)
    ---Purpose: Tests if <me> is linear between its NamedUnknowns.
    ---Level: Advanced 
    returns Boolean
    is deferred;
    
    Simplified(me)
    ---Purpose: Returns a GeneralRelation after replacement of
    --          NamedUnknowns by an associated expression, and after
    --          values computation.
    ---Level: Advanced 
    returns mutable GeneralRelation
    raises NumericError
    is deferred;

    Simplify(me : mutable)
    ---Purpose: Replaces NamedUnknowns by associated expressions,
    --          and computes values in <me>.
    ---Level: Advanced 
    raises NumericError
    is deferred;
    
    Copy(me)
    ---Purpose: Returns a copy of <me> having the same unknowns and 
    --          functions.
    ---Level: Advanced 
    returns mutable like me
    is deferred;
    
    NbOfSubRelations(me)
    ---Purpose: Returns the number of relations contained in <me>.
    ---Level: Internal
    returns Integer
    is deferred;
    
    NbOfSingleRelations(me)
    ---Purpose: Returns the number of SingleRelations contained in 
    --          <me>.
    ---Level: Internal
    returns Integer
    is deferred;
    
    SubRelation(me; index : Integer)
    ---Purpose: Returns the relation denoted by <index> in <me>.
    --          An exception is raised if <index> is out of range.
    ---Level: Internal
    returns any GeneralRelation
    raises OutOfRange
    is deferred;

    Contains(me; exp : GeneralExpression)
    ---Purpose: Tests if <exp> contains <var>.
    ---Level: Internal
    returns Boolean
    is deferred;
    
    Replace(me : mutable ; var : NamedUnknown ; with : GeneralExpression)
    ---Purpose: Replaces all occurences of <var> with <with> in <me>.
    ---Level: Internal
    is deferred;
    
    String(me)
    ---Purpose: returns a string representing <me> in a readable way.
    ---Level: Public
    returns AsciiString
    is deferred;
    
end GeneralRelation;