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Descriptions for patterns.
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‎README.md

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##🐝 Chain Of Responsibility
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**Source:**
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The chain of responsibility pattern is used to process varied requests, each of which may be dealt with by a different handler.
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**Example:**
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```swift
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class MoneyPile {
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let value: Int
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```
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##👫 Command
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The command pattern is used to express a request, including the call to be made and all of its required parameters, in a command object. The command may then be executed immediately or held for later use.
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**Example:**
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```swift
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protocol FileOperationCommand {
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init(file: String)
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##🚧 Iterator
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The iterator pattern is used to provide a standard interface for traversing a collection of items in an aggregate object without the need to understand its underlying structure.
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*No example, yet.*
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##🚧 Mediator
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The mediator pattern is used to reduce coupling between classes that communicate with each other. Instead of classes communicating directly, and thus requiring knowledge of their implementation, the classes send messages via a mediator object.
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*No example, yet.*
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##💾 Memento
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The memento pattern is used to capture the current state of an object and store it in such a manner that it can be restored at a later time without breaking the rules of encapsulation.
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**Example:**
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```swift
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typealias Memento = Dictionary<NSObject, AnyObject>
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```
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##👓 Observer
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The observer pattern is used to allow an object to publish changes to its state.
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Other objects subscribe to be immediately notified of any changes.
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**Example:**
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```swift
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class StepCounter {
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var totalSteps: Int = 0 {
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```
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##🐉 State
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The state pattern is used to alter the behaviour of an object as its internal state changes.
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The pattern allows the class for an object to apparently change at run-time.
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**Example:**
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```swift
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class Context {
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private var state: State = UnauthorizedState()
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```
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##💡 Strategy
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The strategy pattern is used to create an interchangeable family of algorithms from which the required process is chosen at run-time.
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**Example:**
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```swift
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protocol PrintStrategy {
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func printString(string: String) -> String
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```
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##🏃 Visitor
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The visitor pattern is used to separate a relatively complex set of structured data classes from the functionality that may be performed upon the data that they hold.
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**Example:**
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```swift
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protocol PlanetVisitor {
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func visit(planet: PlanetEarth)
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names
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```
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# Creational
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> In software engineering, creational design patterns are design patterns that deal with object creation mechanisms, trying to create objects in a manner suitable to the situation. The basic form of object creation could result in design problems or added complexity to the design. Creational design patterns solve this problem by somehow controlling this object creation.
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##🌰 Abstract Factory
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The abstract factory pattern is used to provide a client with a set of related or dependant objects.
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The "family" of objects created by the factory are determined at run-time.
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**Example:**
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```swift
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// Protocols.
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```
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##👷 Builder
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The builder pattern is used to create complex objects with constituent parts that must be created in the same order or using a specific algorithm.
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An external class controls the construction algorithm.
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**Example:**
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```swift
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protocol ThreeDimensions {
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var x: Double? {get}
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```
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##🏭 Factory Method
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The factory pattern is used to replace class constructors, abstracting the process of object generation so that the type of the object instantiated can be determined at run-time.
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**Example:**
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```swift
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protocol Currency {
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func symbol() -> String
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```
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##🃏 Prototype
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The prototype pattern is used to instantiate a new object by copying all of the properties of an existing object, creating an independent clone.
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This practise is particularly useful when the construction of a new object is inefficient.
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**Example:**
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```swift
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class ThieveryCorporationPersonDisplay {
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var name: String?
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Eduardo.name = "Eduardo"
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```
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##💍 Singleton
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The singleton pattern ensures that only one object of a particular class is ever created.
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All further references to objects of the singleton class refer to the same underlying instance.
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**Example:**
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```swift
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class SingletonClass {
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class var shared : SingletonClass {
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>**Source:** [wikipedia.org](http://en.wikipedia.org/wiki/Structural_pattern)
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##🔌 Adapter
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The adapter pattern is used to provide a link between two otherwise incompatible types by wrapping the "adaptee" with a class that supports the interface required by the client.
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**Example:**
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```swift
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// WARNING: This example uses Point class from Builder pattern!
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**Usage:**
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var tuple = PointConverter.convert(x:1.1, y:2.2, z:3.3, base:2.0, negative:true)
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humanInterface.administerMorphine()
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```
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Info
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====
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🍺 Playground generated with: [playground](https://github.com/jas/playground) by [@jasonsandmeyer](http://twitter.com/jasonsandmeyer)
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🚀 How to generate playground (+zip) from this README: [GENERATE.markdown](https://github.com/ochococo/Design-Patterns-In-Swift/blob/master/GENERATE.markdown)
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📖 Descriptions from: [Gang of Four Design Patterns Reference Sheet](http://www.blackwasp.co.uk/GangOfFour.aspx)
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🚀 How to generate playground (+zip) from this README: [GENERATE.markdown](https://github.com/ochococo/Design-Patterns-In-Swift/blob/master/GENERATE.markdown)

‎docs/behavioral/chain_of_responsibility.md

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##🐝 Chain Of Responsibility
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**Source:**
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The chain of responsibility pattern is used to process varied requests, each of which may be dealt with by a different handler.
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**Example:**
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```swift
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class MoneyPile {
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let value: Int

‎docs/behavioral/command.md

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##👫 Command
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The command pattern is used to express a request, including the call to be made and all of its required parameters, in a command object. The command may then be executed immediately or held for later use.
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**Example:**
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```swift
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protocol FileOperationCommand {
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init(file: String)

‎docs/behavioral/iterator.md

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##🚧 Iterator
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The iterator pattern is used to provide a standard interface for traversing a collection of items in an aggregate object without the need to understand its underlying structure.
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*No example, yet.*

‎docs/behavioral/mediator.md

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##🚧 Mediator
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The mediator pattern is used to reduce coupling between classes that communicate with each other. Instead of classes communicating directly, and thus requiring knowledge of their implementation, the classes send messages via a mediator object.
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*No example, yet.*

‎docs/behavioral/memento.md

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##💾 Memento
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The memento pattern is used to capture the current state of an object and store it in such a manner that it can be restored at a later time without breaking the rules of encapsulation.
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**Example:**
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```swift
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typealias Memento = Dictionary<NSObject, AnyObject>
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‎docs/behavioral/observer.md

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##👓 Observer
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The observer pattern is used to allow an object to publish changes to its state.
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Other objects subscribe to be immediately notified of any changes.
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**Example:**
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```swift
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class StepCounter {
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var totalSteps: Int = 0 {

‎docs/behavioral/state.md

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##🐉 State
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The state pattern is used to alter the behaviour of an object as its internal state changes.
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The pattern allows the class for an object to apparently change at run-time.
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**Example:**
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class Context {
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private var state: State = UnauthorizedState()

‎docs/behavioral/strategy.md

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##💡 Strategy
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The strategy pattern is used to create an interchangeable family of algorithms from which the required process is chosen at run-time.
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**Example:**
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```swift
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protocol PrintStrategy {
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func printString(string: String) -> String

‎docs/behavioral/visitor.md

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##🏃 Visitor
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The visitor pattern is used to separate a relatively complex set of structured data classes from the functionality that may be performed upon the data that they hold.
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**Example:**
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```
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‎docs/creational/abstract_factory.md

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##🌰 Abstract Factory
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The abstract factory pattern is used to provide a client with a set of related or dependant objects.
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The "family" of objects created by the factory are determined at run-time.
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**Example:**
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// Protocols.
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‎docs/creational/builder.md

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##👷 Builder
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The builder pattern is used to create complex objects with constituent parts that must be created in the same order or using a specific algorithm.
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An external class controls the construction algorithm.
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**Example:**
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protocol ThreeDimensions {
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‎docs/creational/factory.md

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##🏭 Factory Method
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The factory pattern is used to replace class constructors, abstracting the process of object generation so that the type of the object instantiated can be determined at run-time.
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**Example:**
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```swift
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protocol Currency {
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func symbol() -> String

‎docs/creational/prototype.md

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##🃏 Prototype
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The prototype pattern is used to instantiate a new object by copying all of the properties of an existing object, creating an independent clone.
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This practise is particularly useful when the construction of a new object is inefficient.
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**Example:**
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```swift
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class ThieveryCorporationPersonDisplay {
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var name: String?

‎docs/creational/singleton.md

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##💍 Singleton
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The singleton pattern ensures that only one object of a particular class is ever created.
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All further references to objects of the singleton class refer to the same underlying instance.
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**Example:**
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‎docs/footer.md

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🍺 Playground generated with: [playground](https://github.com/jas/playground) by [@jasonsandmeyer](http://twitter.com/jasonsandmeyer)
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🚀 How to generate playground (+zip) from this README: [GENERATE.markdown](https://github.com/ochococo/Design-Patterns-In-Swift/blob/master/GENERATE.markdown)
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📖 Descriptions from: [Gang of Four Design Patterns Reference Sheet](http://www.blackwasp.co.uk/GangOfFour.aspx)
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🚀 How to generate playground (+zip) from this README: [GENERATE.markdown](https://github.com/ochococo/Design-Patterns-In-Swift/blob/master/GENERATE.markdown)

‎docs/header.md

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* [Behavioral](#behavioral)
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* [Creational](#creational)
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* [Structural](#structural)
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‎docs/structural/adapter.md

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##🔌 Adapter
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The adapter pattern is used to provide a link between two otherwise incompatible types by wrapping the "adaptee" with a class that supports the interface required by the client.
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**Example:**
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**Usage:**
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‎docs/structural/bridge.md

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##🌉 Bridge
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The bridge pattern is used to separate the abstract elements of a class from the implementation details, providing the means to replace the implementation details without modifying the abstraction.
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‎docs/structural/composite.md

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##🌿 Composite
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The composite pattern is used to create hierarchical, recursive tree structures of related objects where any element of the structure may be accessed and utilised in a standard manner.
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‎docs/structural/decorator.md

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##🍧 Decorator
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The decorator pattern is used to extend or alter the functionality of objects at run- time by wrapping them in an object of a decorator class.
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This provides a flexible alternative to using inheritance to modify behaviour.
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