An introduction to generics

The concept of generics has been around for a while, so it should not be a new concept to developers coming from languages such as Java or C#. The Swift implementation of generics is very similar to these languages. For those developers coming from languages such as Objective-C, which do not have generics, they might seem a bit foreign at first, but once you start using them you will realize how powerful they are.

Generics allow us to write very flexible and reusable code that avoids duplication. With a type-safe language, such as Swift, we often need to write functions or types that are valid for multiple types. For example, we might need to write a function that swaps the values of two variables; however, we may use this function to swap two String types, two Int types, and two Double types. Without generics, we will need to write three separate functions; however, with generics, we can write one generic function to provide the swap functionality for multiple...