Function inside a function.?

Question

This code produces the result as 56.

function x ($y) {
    function y ($z) {
        return ($z*2);
    }

    return($y+3);
}

$y = 4;
$y = x($y)*y($y);
ech         


        

Answer 1

This is useful concept for recursion without static properties , reference etc:

function getRecursiveItems($id){
    $allItems = array();
    
    function getItems($parent_id){
       return DB::findAll()->where('`parent_id` = $parent_id');
    } 
   
    foreach(getItems($id) as $item){
         $allItems = array_merge($allItems, getItems($item->id) );
    }

    return $allItems;
}