PHP 5.4 Pattern Traits

libtraits.php

<?php

namespace traits;

   trait Singleton {    

      // Для тех, кто не предусмотрел конструктор в классе
      private function __construct() {
      
      }
       
      public static function getInstance() {
         static $_instance = NULL;
         $class = __CLASS__;
         return $_instance ?: $_instance = new $class;
      }
       
      public function __clone() {
          trigger_error('Cloning '.__CLASS__.' is not allowed.', E_USER_ERROR);
      }   
   }

   trait Prototype {
      
      private 
            $_props = array(),
            $_methods = array();

      function &__get($name) {
        
         if (array_key_exists($name, $this->_props )) {
            return $this->_props[$name];
         }
         elseif (array_key_exists($name, $this->_methods )) {
            return $this->_methods[$name];
         }
         return null;
      }
          
      function __set($name, $value) {
         
         if (is_object($value) && is_callable($value)) {
            if (!array_key_exists($name, $this->_methods)) {
               $this->_methods[$name] = array();
            }
            
            if($value instanceof \Closure) {
                $value = $value->bindTo($this);
            }
            
            $this->_methods[$name][] = $value;
         }
         else {
            $this->_props[$name] = $value;
         }
      }
          
      function __call($name, $args = array()) {
         
         if (array_key_exists($name, $this->_methods)) {            
            $methods = $this->_methods[$name];
            
            if (is_array($methods)) {
                
                foreach($methods as $method) {             
                    
                    if(!is_null($result = call_user_func_array($method, $args))) {
                        return $result;
                    }
                }
            }
         }
                 
         return null;
      }
   }
   
}

Example:

class MyAwesomeClass {
  use traits\Singleton; // now __construct is private, getInstance should be used instead
  private function __construct($foo, $bar) { // overriding
    echo "$foo is $bar";
  } 
}