In Swift, an efficient function that separates an array into 2 arrays based on a predicate

Question

Note: I\'m currently still using Swift 2.2, but open to Swift 3 solutions as well

I\'m looking to create a function that operates very closely to filter

Answer 1

Swift 4 Solution

partition(by:)

It reorders the origin array and returns start index of subarray satisfies the predicate.

In this example it returns 7.

0..<7 elemets aren't divisible by 3 and 7..n-1 elements are divisible by 3.

 var numbers = [1,2,3,4,5,6,7,8,9,10]
 let partition = numbers.partition(by: { $0 % 3 == 0 })
 let divisibleBy3 = Array(numbers[..