Question

PHP functions such as ‘array_map’ take a callback, which can be a simple function or a class or object method:

$array2 = array_map('myFunc', $array);  

or

$array2 = array_map(array($object, 'myMethod'), $array);

But is there a syntax to pass a method which is bound within the iteration to the current object (like ‘invoke’ in Prototype.js)? So that the following could be used:

$array2 = array_map('myMethod', $array);

with the effect of

foreach($array as $obj) $array2[] = $obj->myMethod();

Obviously I can use this form, or I can write a wrapper function to make the call, and even do that inline. But since ‘myMethod’ is already a method it seems to be going round the houses to have to do one of these.

Answer 1

function obj_array_map($method, $arr_of_objects) {
    $out = array();
    $args = array_slice(func_get_args(), 2);
    foreach ($arr_of_objects as $key => $obj) {
        $out[$key] = call_user_func_array(Array($obj, $method), $args);
    }
    return $out;
}

// this code
$a = Array($obj1, $obj2);
obj_array_map('method', $a, 1, 2, 3);

// results in the calls:
$obj1->method(1, 2, 3);
$obj2->method(1, 2, 3);