3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = [1, 2, 3]; $limit = 10; foreach ($a as &$v) { $a[] = 'x'; var_dump($a); if (--$limit == 0) break; }
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.25, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
array(4) { [0]=> &int(1) [1]=> int(2) [2]=> int(3) [3]=> string(1) "x" } array(5) { [0]=> int(1) [1]=> &int(2) [2]=> int(3) [3]=> string(1) "x" [4]=> string(1) "x" } array(6) { [0]=> int(1) [1]=> int(2) [2]=> &int(3) [3]=> string(1) "x" [4]=> string(1) "x" [5]=> string(1) "x" } array(7) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> &string(1) "x" [4]=> string(1) "x" [5]=> string(1) "x" [6]=> string(1) "x" } array(8) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> string(1) "x" [4]=> &string(1) "x" [5]=> string(1) "x" [6]=> string(1) "x" [7]=> string(1) "x" } array(9) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> string(1) "x" [4]=> string(1) "x" [5]=> &string(1) "x" [6]=> string(1) "x" [7]=> string(1) "x" [8]=> string(1) "x" } array(10) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> string(1) "x" [4]=> string(1) "x" [5]=> string(1) "x" [6]=> &string(1) "x" [7]=> string(1) "x" [8]=> string(1) "x" [9]=> string(1) "x" } array(11) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> string(1) "x" [4]=> string(1) "x" [5]=> string(1) "x" [6]=> string(1) "x" [7]=> &string(1) "x" [8]=> string(1) "x" [9]=> string(1) "x" [10]=> string(1) "x" } array(12) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> string(1) "x" [4]=> string(1) "x" [5]=> string(1) "x" [6]=> string(1) "x" [7]=> string(1) "x" [8]=> &string(1) "x" [9]=> string(1) "x" [10]=> string(1) "x" [11]=> string(1) "x" } array(13) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> string(1) "x" [4]=> string(1) "x" [5]=> string(1) "x" [6]=> string(1) "x" [7]=> string(1) "x" [8]=> string(1) "x" [9]=> &string(1) "x" [10]=> string(1) "x" [11]=> string(1) "x" [12]=> string(1) "x" }
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/uuaj1 on line 2
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[' in /in/uuaj1 on line 2
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/uuaj1 on line 2
Process exited with code 255.

preferences:
297.08 ms | 401 KiB | 355 Q