Erich Gamma、Richard Helm、Ralph Johnson和 John Vlissides(Addison-Wesley Professional, 1994)的 *Design Patterns: Elements of Reusable Object-Oriented Software* 被俗称为 `The Gang of Four book`,是面向对象编程模式的目录。它这样定义面向对象编程:
由 Erich Gamma、Richard Helm、Ralph Johnson和 John Vlissides(Addison-Wesley Professional, 1994)编写的书*Design Patterns: Elements of Reusable Object-Oriented Software* 被俗称为 `The Gang of Four`,它是面向对象编程模式的目录。它这样定义面向对象编程:
> Object-oriented programs are made up of objects. An *object* packages both
> data and the procedures that operate on that data. The procedures are