code: //==============================================================================
  //	
  //	Copyright (c) 2013-
  //	Authors:
  //	* Ernst Moritz Hahn <emhahn@cs.ox.ac.uk> (University of Oxford)
  //	
  //------------------------------------------------------------------------------
  //	
  //	This file is part of PRISM.
  //	
  //	PRISM 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.
  //	
  //	PRISM 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 PRISM; if not, write to the Free Software Foundation,
  //	Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  //	
  //==============================================================================
  
  package param;
  
  /**
   * Function representation using cached functions.
   *
   * @author Ernst Moritz Hahn <emhahn@cs.ox.ac.uk> (University of Oxford)
   * @see CachedFunctionFactory
   */
  final class CachedFunction extends Function {
  	/** unique number of cached function this function represents */
  	private int number;
  	/** factory this function belongs to */
  	private CachedFunctionFactory factory;
  	
  	/**
  	 * Constructs a new cached function.
  	 * 
  	 * @param factory function factory this function belongs to
  	 * @param number unique number of cached function this function represents
  	 */
  	CachedFunction(CachedFunctionFactory factory, int number)
  	{
  		super(factory);
  		this.factory = factory;
  		this.number = number;
  	}
  	
  	/**
  	 * Returns the unique number of the cached function this function represents. 
  	 * 
  	 * @return unique number
  	 */
  	int getNumber()
  	{
  		return number;
  	}
  	
  	@Override
  	public String toString()
  	{
  		return factory.getFunction(number).toString();
  	}
  	
  	@Override
  	public boolean equals(Object obj) {
  		if (!(obj instanceof CachedFunction)) {
  			return false;
  		}
  		CachedFunction function = (CachedFunction) obj;
  		return number == function.number;
  	}
  	
  	@Override
  	public int hashCode() {
  		return number;
  	}
  	
  	@Override
  	public Function add(Function other) {
  		return factory.add(this,  other);
  	}
  
  	@Override
  	public Function negate() {
  		return factory.negate(this);
  	}
  
  	@Override
  	public Function multiply(Function other) {
  		return factory.multiply(this, other);
  	}
  
  	@Override
  	public Function divide(Function other) {
  		return factory.divide(this, other);
  	}
  
  	@Override
  	public Function star() {
  		return factory.star(this);
  	}
  
  	@Override
  	public Function toConstraint() {
  		return factory.toConstraint(this);
  	}
  
  	@Override
  	public BigRational evaluate(Point point, boolean cancel) {
  		return factory.evaluate(this, point, cancel);
  	}
  
  	@Override
  	public BigRational evaluate(Point point) {
  		return factory.evaluate(this, point);
  	}
  
  	@Override
  	public boolean check(Point point, boolean strict) {
  		return factory.check(this, point, strict);
  	}
  
  	
  	@Override
  	public BigRational asBigRational() {
  		return factory.asBigRational(this);
  	}
  
  	@Override
  	public boolean isNaN() {
  		return factory.isNaN(this);
  	}
  
  	@Override
  	public boolean isInf() {
  		return factory.isInf(this);
  	}
  
  	@Override
  	public boolean isMInf() {
  		return factory.isMInf(this);
  	}
  
  	@Override
  	public boolean isOne() {
  		return factory.isOne(this);
  	}
  
  	@Override
  	public boolean isZero() {
  		return factory.isZero(this);
  	}
  
  	@Override
  	public boolean isConstant()
  	{
  		return factory.isConstant(this);
  	}
  }
  