<?php
 
class A
{
    private $_a;
    private $_b;
 
    public function __construct($a = null, $b = null)
    {
        $this->_a = $a;
        $this->_b = $b;
 
        echo 'Constructed A instance with args: ' . $a . ', ' . $b . "\n";
    }
 
    public function construct_from_this()
    {
        $ref = new ReflectionClass($this);
        return $ref->newInstance('a_value', 'b_value');
    }
}
 
$foo = new A();
$result = $foo->construct_from_this();

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