3v4l.org

run code in 300+ PHP versions simultaneously
<?php $foo = null; var_dump($foo === null); var_dump(is_null($foo)); $bar = array('x' => 'x'); var_dump(isset($bar['x'])); var_dump(array_key_exists('x', $bar)); var_dump(isset($baz) ? $baz : null); var_dump($baz);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
bool(true) bool(true) bool(true) bool(true) NULL Warning: Undefined variable $baz in /in/07BVM on line 12 NULL
Output for 5.0.4 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.3.33, 7.4.0 - 7.4.25, 7.4.27 - 7.4.33
bool(true) bool(true) bool(true) bool(true) NULL Notice: Undefined variable: baz in /in/07BVM on line 12 NULL
Output for 7.3.32, 7.4.26
bool(true) bool(true) bool(true) bool(true) NULL NULL
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.3
bool(true) bool(true) bool(true) bool(true) NULL Notice: Undefined variable: baz in /in/07BVM on line 12 NULL

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214.08 ms | 410 KiB | 5 Q