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<?php class Foo { private $number = 42; public function bar() { var_dump($this->number); return __METHOD__; } } class Bar extends Foo { public function callme($callback) { echo call_user_func($callback); } } $callback = array('Foo', 'Bar'); var_dump(is_callable($callback)); $bar = new Bar(); $bar->callme($callback);

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34.04 ms | 402 KiB | 5 Q