play with proxy function with invoke php

proxy.php

<?php

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

function node_load($param) {
  echo $param;
}

class ProxyFunction {

  var $fn_name;

  /**
   *
   * @var Array 
   */
  var $before = array();

  /**
   *
   * @var Array
   */
  var $after = array();

  /**
   *
   * @var Array
   */
  var $args = array();

  public function __construct($fn_name) {
    $this->fn_name = $fn_name;
  }

  function before($fn) {
    $this->before[] = $fn;
    return $this;
  }

  function after($fn) {
    $this->after[] = $fn;
    return $this;
  }

  function cycleBefore() {
    foreach ($this->before as $fn) {
      call_user_func_array($fn, $this->args);
    }
  }

  function cycleAfter() {
    foreach ($this->after as $fn) {
      call_user_func_array($fn, $this->args);
    }
  }

  function __invoke() {
    $this->args = func_get_args();
    $this->cycleBefore();
    call_user_func_array($this->fn_name, $this->args);
    $this->cycleAfter();
  }

}

$node_load = (new ProxyFunction("node_load"))
  ->before(function() {
      echo "before";
    })
  ->after(function () {
    echo "after";
  });


$node_load(22);
?>