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Common Design Patterns

Design patterns are solutions to software design problems you find again and again in real-world application development. Patterns are about reusable designs and interactions of objects.

The 23 Gang of Four (GoF) patterns are generally considered the foundation for all other patterns. They are categorized in three groups: Creational, Structural, and Behavioral (for a complete list see below).

To give you a head start, the xtd C++ source code for each pattern is provided in structural form. Structural code uses type names as defined in the pattern definition and UML diagrams.

Notes

The Common Design Patterns are adapted to modern C++ and follow the std standard.

You can see the original source : C# Design Patterns.

Creational Patterns

  • Abstract Factory Creates an instance of several families of classes
  • Builder Separates object construction from its representation
  • Factory Method Creates an instance of several derived classes
  • Prototype A fully initialized instance to be copied or cloned
  • Singleton A class of which only a single instance can exist

Structural Patterns

  • Adapter Match interfaces of different classes
  • Bridge Separates an object’s interface from its implementation
  • Composite A tree structure of simple and composite objects
  • Decorator Add responsibilities to objects dynamically
  • Facade A single class that represents an entire subsystem
  • Flyweight A fine-grained instance used for efficient sharing
  • Proxy An object representing another object

Behavioral Patterns

  • Chain of Responsibility A way of passing a request between a chain of objects
  • Command Encapsulate a command request as an object
  • Interpreter A way to include language elements in a program
  • Iterator Sequentially access the elements of a collection
  • Mediator Defines simplified communication between classes
  • Memento Capture and restore an object's internal state
  • Observer A way of notifying change to a number of classes
  • State Alter an object's behavior when its state changes
  • Strategy Encapsulates an algorithm inside a class
  • Template Method Defer the exact steps of an algorithm to a subclass
  • Visitor Defines a new operation to a class without change

See also