Array destructuring
-----
<?php

[$a, $b] = [$c, $d];
[, $a, , , $b, ,] = $foo;
[, [[$a]], $b] = $bar;
['a' => $b, 'b' => $a] = $baz;
-----
!!php7
[$a, $b] = [$c, $d];
[, $a, , , $b, ] = $foo;
[, [[$a]], $b] = $bar;
['a' => $b, 'b' => $a] = $baz;