In this Swift tutorial, you will learn how to use the flatMap function in Swift which will flatten an Array of Arrays into a single array of elements.
Given an Array of Arrays
Let’s consider the following Array of Arrays.
let numbers = [ [1,2,3,4], [5,6,7,8], [9,10,11,12]]
The above array contains 3 arrays of integers. We can use flatMap function to flatten this array of arrays into a single array of numbers.
FlatMap Example in Swift
Below is an example of how you can use the flatMap function in Swift.
let numbers = [ [1,2,3,4], [5,6,7,8], [9,10,11,12]]
let flattenArrayOfNumbers = numbers.flatMap { $0 }
print(flattenArrayOfNumbers)
If you run the above code example in Xcode Playground you will get the following result.
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
and here is a screenshot of my Xcode playground with the above Swift code demonstrating how flatMap function works.
I hope this code example was helpful to you. If you are interested to learn how the map(_:) function works in Swift, check this blog post: How to use map(_:) in Swift.