Chainable.class.php

<?php

	/**
	 * Class Chainable
	 * Wrapper for convenient chaining methods
	 *
	 * @author Stefano Azzolini <lastguest@gmail.com>
	 */
	class Chainable {
		private $instance = null;
		private $_returns = [];

		/**
		 * Constructor accepts object instances or class name string with optionals instance contructor parameters
		 */
		public function __construct(){
			$pars = func_get_args();
			$this->instance = is_object($obj=array_shift($pars))?$obj:new $obj($pars);
		}

		/**
		 * Retrieve the returned value from last chained method
		 * @param  mixed $var The var container for the returned value
		 * @return Chainable      Pass the Chainable instance for method chaining.
		 */
		public function _get_return(&$var){
			$var = count($this->_returns)?array_pop($this->_returns):null;
			return $this;
		}

		/**
		 * Clear the returned value cache
		 * @return Chainable      Pass the Chainable instance for method chaining.
		 */
		public function _reset(){
			$this->_returns = [];
			return $this;
		}

		/**
		 * Method calling handler, this magic method pass the call to the embedded instance.
		 * @return Chainable      Pass the Chainable instance for method chaining.
		 */
		public function __call($n,$p){
			($r=call_user_func_array([$this->instance,$n],$p))?$this->_returns[]=$r:null;
			return $this;
		}

	}


	/**
	*	Example
	*/

	class Test {
		function foo(){ echo "FOO"; }
		function baz(){ return "BAZ"; }
		function bar(){ echo "BAR"; }
	}

	// Create a new chainable instance of Test
	$t = new Chainable('Test');
	$t
		->foo()
		->baz() ->_get_return($the_value) // retrieve the returned value
		->bar();

	echo "\n\n",'The value was : ',$the_value;