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run code in 300+ PHP versions simultaneously
<?php function do_action_ref_array( $callback, $args ) { var_dump($args); //$args[0] = 'b'; call_user_func_array( $callback, array_slice( $args, 0, 2 ) ); } function filter( $arg1, &$arg2 ) { var_dump( $arg1, $arg2 ); return $arg1; }; class Test { public function run() { do_action_ref_array( 'filter', [1, &$this] ); } } $object = new Test(); $object->run();
based on UegDO
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.24, 7.4.0 - 7.4.12, 8.0.0
array(2) { [0]=> int(1) [1]=> object(Test)#1 (0) { } } int(1) object(Test)#1 (0) { }
Output for 7.1.25 - 7.1.33
array(2) { [0]=> int(1) [1]=> object(Test)#1 (0) { } } Warning: Parameter 2 to filter() expected to be a reference, value given in /in/DCCeh on line 6 int(1) object(Test)#1 (0) { }
Output for 5.6.38, 7.0.33
array(2) { [0]=> int(1) [1]=> &object(Test)#1 (0) { } } int(1) object(Test)#1 (0) { }