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run code in 300+ PHP versions simultaneously
<?php $a = new stdClass(); $a->b = 1; $a->c = 2; $a->d = 3; var_dump(key($a)); next($a); var_dump(key($a));
Output for 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
Deprecated: key(): Calling key() on an object is deprecated in /in/BhY0Q on line 8 string(1) "b" Deprecated: next(): Calling next() on an object is deprecated in /in/BhY0Q on line 9 Deprecated: key(): Calling key() on an object is deprecated in /in/BhY0Q on line 10 string(1) "c"
Output for 7.1.25 - 7.1.31, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30
string(1) "b" string(1) "c"
preferences:
107.04 ms | 402 KiB | 174 Q