Swift Array appending (the functional way)

Array+Appending.swift

public extension Array {

    /// Adds the elements of a sequence to the end of the array and returns a copy of it.
    ///
    /// This example creates a new array containing the elements of a
    /// `Range<Int>` instance added to an array of integers
    ///
    ///     let array = [1, 2, 3, 4, 5]
    ///     let numbers = array.appending(contentsOf: 10...15)
    ///     print(numbers)
    ///     // Prints "[1, 2, 3, 4, 5, 10, 11, 12, 13, 14, 15]"
    ///
    /// - Parameter newElements: The elements to append to the array.
    /// - Returns: The new array containing every element
    func appending<S>(contentsOf newElements: S) -> Array where Element == S.Element, S: Sequence {
        var copy = self
        copy.append(contentsOf: newElements)
        return copy
    }

    /// Adds the given element to the end of the array and returns a copy of it.
    ///
    /// This example creates a new array containing the new element
    ///
    ///     let array = [1, 2, 3, 4, 5]
    ///     let numbers = array.appending(6)
    ///     print(numbers)
    ///     // Prints "[1, 2, 3, 4, 5, 6]"
    ///
    /// - Parameter newElement: The element to append to the array.
    /// - Returns: The new array containing the new element
    func appending(_ newElement: Self.Element) -> Array {
        var copy = self
        copy.append(newElement)
        return copy
    }
}