Swift: first and last element of an array

extension Array {
    
    var first: T? {
        if isEmpty {
            return nil
        }
        
        return self[0]
    }
    
    var last: T? {
        if isEmpty {
            return nil
        }
        
        return self[count - 1]
    }
    
}


let array = [1, 2, 3, 4, 5]

array.first // => {Some 1}
array.last  // => {Some 5}


let emptyArray: Any[] = []

emptyArray.first // => nil
emptyArray.last  // => mil