<?php

class ComParametro
{
   public function __construct($parametro)
   {}
}


class SemParametro
{
    public function __construct(){}
}

new ComParametro($a = 'a');


print_r($a);


new SemParametro($b = 'b');


print_r($b);


new stdClass($c = 'c');


print_r($c);