Description:
------------
Add the magic method __toNumber.

Reproduce code:
---------------
class Number
{
   private $number;
 
   //some useful example methods
   function isBetween($a, $b) { //is number between ? }
   //etc

   function __toNumber()
   {
     return $this->number;
   }
}

Expected result:
----------------
$c = new Number(3);

echo $c; //outputs: 3
var_dump($c->isBetween(2, 4)) //returns true

//cast it too a Price object (extended from Number)
$price = (Price) $c;

//override __toNumber()
echo $c; //outputs 3.00 for example