/**
 * visitor.h
 * Implemented by Blueprint Technologies, Inc.
 */

#ifndef _visitor_h
#define _visitor_h

/**
 * Forward declarations.
 */

class Element;
class ConcreteElement;

/**
 * Declares a visit operation for each class of ConcreteElement
 * in the object structure. The operation's name and signature
 * identifies the class that sends the Visit request to the visitor.
 */

class Visitor
{

public:
	void visitConcreteElement( ConcreteElement* ) = 0;

};

/**
 * Implements each operation declared by Visitor.
 */

class ConcreteVisitor: public Visitor
{

public:
	void visitConcreteElement( ConcreteElement* element )
	{
	};
};

/**
 * Defines an Accept operation that takes a visitor as an argument.
 */

class Element
{

public:
	void accept( Visitor* ) = 0;

};

/**
 * Implements an Accept operation that takes a visitor as an argument.
 */

class ConcreteElement: public Element
{

public:
	void accept( Visitor* visitor )
	{
	};
};

#endif