Chaining.php

<?php 
class Math 
{
	protected $result = 0;

	public function plus($value)
	{
		$this->result += $value;

		return $this;
	}

	public function minus($value)
	{
		$this->result -= $value;

		return $this;
	}

	public function result()
	{
		return $this->result;
	}

}

$cmobj = new Math();

/* Common */

$cmobj->plus(10);
$cmobj->minus(2);
echo $cmobj->result(); // 8

/* Using method chaining */

$mcobj = new Math();

echo $mcobj->plus(13)->minus(3)->result(); //10