将PHP匿名函数规范为5.2

Question

need help on regulating anonymous function. cant get through this one..

$marks = implode(',', array_map(function() {
                            return '?';
                        }, explode(',', $props)));

How can i convert this to be compatible with php 5.2?

Answer 1

php 5.2 don't support lambada:

function callback($value)
{
    return '?';
}

$marks = implode(',', array_map('callback', explode(',', $props)));