attic/View.php
public function __isset($name)
    {
        return ($name && parent::__isset($name)) || isset($this->params[$name]);
    }
public function __isset($name)
    {
        return ($name && parent::__isset($name)) || isset($this->params[$name]);
    }
public function __isset ( $ name ) { return ( $ name && parent :: __isset ( $ name ) ) || isset ( $ this -> params [ $ name ] ) ; }
Magic is set checker.

@param string $name the property or param name to check

@return bool whether the value is set
Magic is set checker .