/*

     This file is part of Combean.

     Combean is free software; you can redistribute it and/or modify

     it under the terms of the GNU General Public License as published by

     the Free Software Foundation; either version 2 of the License, or

     (at your option) any later version.

     Combean is distributed in the hope that it will be useful,

     but WITHOUT ANY WARRANTY; without even the implied warranty of

     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

     GNU General Public License for more details.

     You should have received a copy of the GNU General Public License

     along with Foobar; if not, write to the Free Software

     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 */

 package net.sourceforge.combean.mathprog.grooml;

 import net.sourceforge.combean.mathprog.grooml.GSet;

 /**

  * A set with a dynamic definition that is evaluated when the elements of the

  * set are being accessed.

  */

 class GDynamicSet extends GSet {

     private Closure genSet;

     /**

      * Constructor

      * 

      * @params genSet the closure that defines the set (must return a value that

      * is convertable to a set)

      */

     public GDynamicSet(Closure genSet) {

         this.genSet = genSet;

     }

     public Iterator evaluate(Object env) {

         this.genSet.delegate = env;

         Object setDef = null;

         use (GModelArithmeticCategory) {

                 setDef = this.genSet.call();

         }

         return GSet.convert(setDef).evaluate(env);

     }

     public String toString() {

         String result = "dynSet { ${genSet.class.name} }";

         return result;

     }

 }