PHP "method overloading" example

<?php

class Foo
{
    public function bar()
    {
        $argsCount = func_num_args();
        switch ($argsCount) {
            case 1:
                return $this->_barWithOneArgument(func_get_arg(0));
                break;
            case 2:
                return $this->_barWithTwoArguments(func_get_arg(0), func_get_args(1));
                break;
            default:
                throw new InvalidArgumentException();
        }
    }

    private function _barWithOneArgument($a)
    {
        return "Hello, I'm one argument function";
    }

    private function _barWithTwoArguments($a, $b)
    {
        return "Hello, I'm function with two arguments";
    }
}

$foo = new Foo();
var_dump($foo->bar(1));
var_dump($foo->bar(1, 2));