Created functions to make possible to create static methods on models

core/MY_Model.php

@@ -937,4 +937,60 @@ protected function _return_type($multi = FALSE)
         $method = ($multi) ? 'result' : 'row';
         return $this->_temporary_return_type == 'array' ? $method . '_array' : $method;
     }
-}
+
+    /**
+     * Return the class name of the current call
+     * @param boolean $bt
+     * @param integer $l
+     * @return type
+     */
+    static function get_called_class($bt = false, $l = 1) {
+        if (!$bt) $bt = debug_backtrace();
+        if (!isset($bt[$l])) throw new Exception("Cannot find called class -> stack level too deep.");
+        if (!isset($bt[$l]['type']))
+            throw new Exception ('type not set');
+        else switch ($bt[$l]['type']){
+            case '::':
+                $lines = file($bt[$l]['file']);
+                $i = 0;
+                $callerLine = '';
+                do{
+                    $i++;
+                    $callerLine = $lines[$bt[$l]['line']-$i] . $callerLine;
+                } while (stripos($callerLine,$bt[$l]['function']) === false);
+                preg_match('/([a-zA-Z0-9\_]+)::'.$bt[$l]['function'].'/', $callerLine, $matches);
+                if (!isset($matches[1]))
+                    throw new Exception ("Could not find caller class: originating method call is obscured.");
+                switch ($matches[1]){
+                    case 'self':
+                    case 'parent':
+                        return self::get_called_class($bt,$l+1);
+                    default:
+                        return $matches[1];
+                }
+            case '->': switch ($bt[$l]['function']){
+                    case '__get':
+                        if (!is_object($bt[$l]['object'])) throw new Exception ("Edge case fail. __get called on non object.");
+                        return get_class($bt[$l]['object']);
+                    default: return $bt[$l]['class'];
+                }       
+            default: throw new Exception ("Unknown backtrace method type");
+        }
+    }
+
+    /**
+     * This will keep a instance of the current class to be used on static methods, like singleton
+     * @var Current_class 
+     */
+    private static $_instance;
+
+    /**
+     * Return a instance of the current class to be used on static methods
+     * @return class_instance
+     */
+    static function getInstance(){
+        if (self::$_instance == null)
+            eval("self::\$_instance = new ".(self::get_called_class())."();");
+        return self::$_instance;
+    }
+}