3v4l.org

run code in 300+ PHP versions simultaneously
<?php var_dump(preg_match('/[]/', 'foo 42 [ bar', $m), $m);
Output for 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Warning: preg_match(): Compilation failed: missing terminating ] for character class at offset 2 in /in/cT2OY on line 2 bool(false) NULL
Output for 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6
Warning: preg_match(): Compilation failed: missing terminating ] for character class at offset 2 in /in/cT2OY on line 2 bool(false) array(0) { }
Output for 4.3.0 - 4.3.10
Warning: Compilation failed: missing terminating ] for character class at offset 2 in /in/cT2OY on line 2 bool(false) array(0) { }

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269.99 ms | 401 KiB | 351 Q