1list()
2-----
3<?php
4
5list() = $a;
6list($a) = $b;
7list($a, $b, $c) = $d;
8list(, $a) = $b;
9list(, , $a, , $b) = $c;
10list(list($a)) = $b;
11list(, list(, list(, $a), $b)) = $c;
12-----
13list() = $a;
14list($a) = $b;
15list($a, $b, $c) = $d;
16list(, $a) = $b;
17list(, , $a, , $b) = $c;
18list(list($a)) = $b;
19list(, list(, list(, $a), $b)) = $c;
20