Description:
------------
I would really like to have something like a better handling of array, strings, numbers and so on.
Look at my examples, you will understand better what i mean

Test script:
---------------
<?php
$a = [2, 3, 4, 5]; // I define an array as for php 5.4
$a = $a->map(function($el) { // $a = array_map(callback, $a);
   return $el +1;
});

$b = "Hello";
$b = $b->substr(0, -1); // $b = substr($b, 0, -1);

$c = [2, 3];
$c = $c->merge([4, 5]); // $c = array_merge($c, [4, 5]);

$d = 22 + [2, 3, 4, 5, 6]; // $d = 22 + 2 + 3 + 4 + 5 + 6

$a[] = $b;
$a[] = $c;
$a[] = $d;

// i also would like to have a built-in swap function like this:
$a->swap($b); // $a is $b and $b is $a 

Expected result:
----------------
$a should be [3, 4, 5, 6, "Hell", [2, 3, 4, 5], 42];
$b should be "Hell";
$c should be [2, 3, 4, 5];
$d should be The answer to universe, life and everything; // 42