Visitor
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Revision as of 07:56, 30 July 2008
Introduction
The Visitor is a behavioural pattern. It allows the designer to define new operations on an object structure and its elements, without modifying the object structure itself.
Description
The Visitor describes three major roles:
- Object Structure: Provides a visitor with access to its elements
- Element: Accepts visits
- Visitor: Accesses an element to perform operations