How to use an object method as a callback function

Question

I have the below method in a singleton class

private function encode($inp)
{
    if (is_array($inp) {
        return array_map(\'$this->encode\', $inp);
          


        

Answer 1

From PHP Manual on Callbacks:

A method of an instantiated object is passed as an array containing an object at index 0 and the method name at index 1.

So try

return array_map(array($this, 'encode'), $inp);