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run code in 300+ PHP versions simultaneously
<?php class Promise { public $value; public function __construct($value) { $this->value = $value; } public function when(callable $callable) { $value = $this->value; $callable($value); } } $promise = new Promise(new StdClass); var_dump($promise); $promise->when(function(&$when) { $when = 42; }); var_dump($promise);
Output for 5.5.0 - 5.5.35, 5.6.0 - 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
object(Promise)#1 (1) { ["value"]=> object(stdClass)#2 (0) { } } object(Promise)#1 (1) { ["value"]=> object(stdClass)#2 (0) { } }
preferences:
71.74 ms | 408 KiB | 5 Q