1--TEST-- 2Test array_walk_recursive() function : usage variations - buit-in function as callback 3--FILE-- 4<?php 5/* Prototype : bool array_walk_recursive(array $input, string $funcname [, mixed $userdata]) 6 * Description: Apply a user function to every member of an array 7 * Source code: ext/standard/array.c 8*/ 9 10/* 11 * Passing different buit-in functionns as callback function 12 * pow function 13 * min function 14 * echo language construct 15*/ 16 17echo "*** Testing array_walk_recursive() : built-in function as callback ***\n"; 18 19$input = array(array(2 => 1, 65), array(98, 100), array(6 => -4)); 20 21echo "-- With 'pow' built-in function --\n"; 22var_dump( array_walk_recursive($input, 'pow')); 23 24echo "-- With 'min' built-in function --\n"; 25var_dump( array_walk_recursive($input, "min")); 26 27echo "-- With 'echo' language construct --\n"; 28var_dump( array_walk_recursive($input, "echo")); 29 30echo "Done" 31?> 32--EXPECTF-- 33*** Testing array_walk_recursive() : built-in function as callback *** 34-- With 'pow' built-in function -- 35bool(true) 36-- With 'min' built-in function -- 37bool(true) 38-- With 'echo' language construct -- 39 40Warning: array_walk_recursive() expects parameter 2 to be a valid callback, function 'echo' not found or invalid function name in %s on line %d 41NULL 42Done 43