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<?php $a = 'foo'; echo PHP_EOL, 'unset cast', PHP_EOL; var_dump((unset) $a); var_dump($a); echo PHP_EOL, 'unset call', PHP_EOL; unset($a); var_dump($a);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Fatal error: The (unset) cast is no longer supported in /in/PqkIG on line 6
Process exited with code 255.
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
Deprecated: The (unset) cast is deprecated in /in/PqkIG on line 6 unset cast NULL string(3) "foo" unset call Notice: Undefined variable: a in /in/PqkIG on line 10 NULL
Output for 7.3.32 - 7.3.33
unset cast NULL string(3) "foo" unset call NULL
Output for 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33
unset cast NULL string(3) "foo" unset call Notice: Undefined variable: a in /in/PqkIG on line 10 NULL

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