public function __isset($prop) {
        if (in_array($prop, $this->properties)) {
            return isset($this->$prop);
        }
        throw new \coding_exception("Invalid property $prop specified");
    }
public function __isset($prop) {
        if (in_array($prop, $this->properties)) {
            return isset($this->$prop);
        }
        throw new \coding_exception("Invalid property $prop specified");
    }
public function __isset ( $ prop ) { if ( in_array ( $ prop , $ this -> properties ) ) { return isset ( $ this -> $ prop ) ; } throw new \ coding_exception ( "Invalid property $prop specified" ) ; }
Magic method to check if property is set.

@param string $prop name of property to check.
@return bool
@throws \coding_exception
Magic method to check if property is set .