<?php

class variable {
	var $name;
	var $instantiated;
	var $instantiation;

	function variable($name){
		$this->name = $name;
		$this->instantiated = "false";	
	}
	
	function instantiate($atom){
		if(get_class($atom) == "atom"){
			$this->instantiated	= "true";
			$this->instantiation = $atom;
		}	
	}
	
	function toString(){
		if($this->instantiated == "true"){
			return $atom->toString();	
		}
		else{
			return $this->name;	
		}	
	}
}
?>