Visitor(Chapter 15 of Pro Objective-C Design Patterns for iOS)

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mb5fe55afb6fa16 2012-05-03 13:48:00

文章标签 Objective-C Design Pattern 编程题目 文章分类 后端开发

The Visitor pattern represents an operation to be performed on the elements of an object structure. Visitor lets you define a new operation without changing the classes of the elements on which it operates.

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Visitor(Chapter 15 of Pro Objective-C Design Patterns for iOS)

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