Almost every Swift program uses collections in one way or another. Whether it's to store values to be displayed in some form of list, to keep track of observers, or caching data - collections are everywhere. This week, let's take a look at some of the standard library APIs that let us easily transform collections in a very functional way.
When creating collections of objects or values in Swift, we usually use data structures provided by the standard library - such as Array, Dictionary and Set. While those three cover most use cases, sometimes creating a custom wrapper collection can enable us to make our code more predictable and less prone to errors.