How to Use Generics in Swift

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by The Captain

on
April 15, 2023

How to Use Generics in Swift

Generics are one of the most important features of Swift, allowing us to write flexible, reusable code that can work with different types. In this tutorial, we’ll explore how to use generics in Swift and show you a code snippet to get you started.

What are Generics?

Generics are a way to write code that can work with different types at the same time. They allow us to write flexible, reusable code that can be used in a wide range of situations. Generics are often used in Swift to write collection types, like arrays and dictionaries, but they can be used in many other contexts as well.

How to Use Generics in Swift

Using generics in Swift is relatively easy. To get started, we need to define a placeholder type using angle brackets (< >). This type can then be replaced by any other type we want to use when the code is executed. Here’s an example:

func swap<T>(_ a:inout T,_ b:inout T) {
    // Swap two values of the same type
    let temporaryA = a; a = b; b = temporaryA;
}

In this example, we’ve defined a function called swap that takes two arguments of type T. The function then swaps the values of a and b. The great thing about this code is that we can use it with any type that supports assignment, not just integer types.

Conclusion

Generics are one of the most powerful features of Swift, allowing us to write flexible, reusable code that can be used in a wide variety of situations. With the simple code snippet we’ve shown you here, you can start using generics in your own projects right away.