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run code in 300+ PHP versions simultaneously
<?php function do_action_ref_array( $callback, $args ) { call_user_func_array( $callback, array_slice( $args, 0, 2 ) ); } $function = function( $arg1, &$arg2 ) { return $arg1; }; $args = [1, 2, 3]; do_action_ref_array( $function, $args );
based on P7Akn
Output for 8.0.0
Warning: {closure}(): Argument #2 ($arg2) must be passed by reference, value given in /in/qeUZt on line 4
Output for 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 - 7.3.24, 7.4.0 - 7.4.12
Warning: Parameter 2 to {closure}() expected to be a reference, value given in /in/qeUZt on line 4