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run code in 300+ PHP versions simultaneously
<?php // inspired by discussion at: http://stackoverflow.com/questions/11158772/assigning-null-to-a-variable-in-php-what-does-that-do $a = 1; $a = null; echo isset($a) ? 'true' : 'false', "\n"; // false var_dump($a); // 'NULL' -- but no error notice - bug ? type changed to NULL unset($a); // now variable undefined var_dump($a); // error notice and value NULL echo isset($a) ? 'true' : 'false', "\n"; // false
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
false NULL Warning: Undefined variable $a in /in/rHa1N on line 8 NULL false
Output for 5.0.4 - 5.0.5, 5.1.1 - 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, 7.4.0 - 7.4.33
false NULL Notice: Undefined variable: a in /in/rHa1N on line 8 NULL false
Output for 7.3.32 - 7.3.33
false NULL NULL false
Output for 5.1.0
Fatal error: fatal flex scanner internal error--end of buffer missed in /in/rHa1N on line 9
Process exited with code 255.
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.3
false NULL Notice: Undefined variable: a in /in/rHa1N on line 8 NULL false
preferences:
268.02 ms | 402 KiB | 460 Q