<?php
class ap {
	public function ap_call() {
        echo "\t", get_called_class(), "\n";
	}
	
	public function ap_sub_call_p() {
		$p = new p;
		
		$p->p_call();
	}
	
	public function ap_sub_call_c() {
		$c = new c;
		
		$c->c_call();
	}
}

class p extends ap{
	public function p_call() {
        echo "\t", get_called_class(), "\n";
	}
	
	public function p_parent_call_ap() {
		$ap = new ap;
		
		$ap->ap_call();
	}
	
	public function p_sub_call_c() {
		$c = new c;
		
		$c->c_call();
	}
}

class c extends p {
	public function c_call() {
        echo "\t", get_called_class(), "\n";
	}
	
	public function c_parent_call_p() {
		$p = new p;
		
		$p->p_call();
	}
	
	public function c_parent_call_ap() {
		$ap = new ap;
		
		$ap->ap_call();
	}
}

$ap = new ap;
$p  = new p;
$c  = new c;

echo "These are called in/from ap:\n";
$ap->ap_call();
$ap->ap_sub_call_p();
$ap->ap_sub_call_c();

echo "\n\nThese are called in/from p:\n";
$p->p_call();
$p->p_parent_call_ap();
$p->p_sub_call_c();
echo "These are inherit from ap:\n";
$p->ap_call();
$p->ap_sub_call_p();
$p->ap_sub_call_c();

echo "\n\nhese are called in/from c:\n";
$c->c_call();
$c->c_parent_call_ap();
$c->c_parent_call_p();

echo "These are inherit from p:\n";
$c->p_call();
$c->p_parent_call_ap();
$c->p_sub_call_c();

echo "These are inherit from ap:\n";
$c->ap_call();
$c->ap_sub_call_p();
$c->ap_sub_call_c();

/*
    result:
    
    These are called in/from ap:
	ap
	p
	c


These are called in/from p:
	p
	ap
	c
These are inherit from ap:
	p
	p
	c


hese are called in/from c:
	c
	ap
	p
These are inherit from p:
	c
	ap
	c
These are inherit from ap:
	c
	p
	c
*/