Hamdouchi Interactive
  • Welcome
  • Mobile
  • Tech Blog
  • Let's Talk

Unlocking the Power of Swift:
A Tech Blog Series

Welcome to our tech blog series dedicated to exploring the world of Swift and its related topics. Our goal is to provide valuable insights and in-depth analysis on the latest advancements in the Swift programming language, including design patterns and data structures. Stay tuned for our upcoming articles and join the discussion on the exciting world of Swift programming!

Explore all Topics

What the heck is “associatetype” in Swift?

12/24/2022

0 Comments

 
Picture
An associative type in Swift is a type that is associated with a protocol. This means that the type can be specified as a placeholder for another type, and the actual type that is used will be determined when the protocol is implemented.

For example, consider a protocol called Container that defines a type called Item:

    
​Here, the Item type is an associative type, because it is associated with the Container protocol. This means that when we implement the Container protocol, we can specify the actual type that will be used for the Item type. For example, we could implement the Container protocol like this:

    
In this example, we have implemented the Container protocol for a stack of generic type. We have specified that the Item type will be Generic by using the typealias keyword. This means that wherever the Item type is used in the Container protocol, it will be replaced with the Generic type.
​
Using associative types in this way allows us to create generic protocols that can be implemented with different types. This can be useful for creating reusable components that can be used in different contexts, and it allows us to take advantage of the type safety features of Swift.

Let's see an example of the Int Implementation:

    
Using the same stack, let's see an implementation of a String Type:

    

Another example of how we can use an associatetype in a protocol.

​Imagine that we have a protocol called DataSource that defines a type called Data, and provides a function for retrieving data from the source:

    
We can implement this protocol in different ways depending on the type of data that we want to retrieve. For example, we could create a FileDataSource that retrieves data from a file on disk:

    
​In this implementation, we have specified that the Data type will be String, so the getData() function will return a string. We can also create other implementations of the DataSource protocol that use different types for the Data type. For example, we could create a NetworkDataSource that retrieves data from a network resource:

    
In this implementation, we have specified that the Data type will be a dictionary, so the getData() function will return a dictionary.

Using associative types in this way allows us to create protocols that are flexible and can be implemented in different ways, depending on the specific needs of the application. This can be useful for creating reusable components that can be used in different contexts, and it allows us to take advantage of the type safety features of Swift.
0 Comments
    Picture

    Mohamed Hamdouchi


    Author

    Lead iOS Engineer.
    I help develop Design System Libraries.
    Creative Thinker.
    Featured on the App Store with 4M+ downloads.


    Archives

    May 2023
    April 2023
    March 2023
    February 2023
    January 2023
    December 2022


    Categories

    All
    Abstract Factory
    Associatetype
    Behavioral
    Bridge
    Builder
    Chain Of Responsibility
    Class
    Command
    Composite
    Creational
    Decorator
    Design Pattern
    Facade
    Factory
    Factory Method
    Flyweight
    Interpreter
    Iterator
    Memento
    Observer
    Protocol
    Prototype
    Proxy
    Singleton
    State
    Strategy
    Struct
    Structural
    Swift

​​COPYRIGHT © 2009 HAMDOUCHI INTERACTIVE, LLC. ​ALL RIGHTS RESERVED
  • Welcome
  • Mobile
  • Tech Blog
  • Let's Talk