public function exists($alias)
    {
        $repo = $this->getItemsName();
        $loc = &$this->$repo;
        foreach (explode('.', $alias) as $step) {
            if (!isset($loc[$step])) {
                return false;
            } else {
                $loc = &$loc[$step];
            }
        }
        return true;
    }
public function exists($alias)
    {
        $repo = $this->getItemsName();
        $loc = &$this->$repo;
        foreach (explode('.', $alias) as $step) {
            if (!isset($loc[$step])) {
                return false;
            } else {
                $loc = &$loc[$step];
            }
        }
        return true;
    }
public function exists ( $ alias ) { $ repo = $ this -> getItemsName ( ) ; $ loc = & $ this -> $ repo ; foreach ( explode ( '.' , $ alias ) as $ step ) { if ( ! isset ( $ loc [ $ step ] ) ) { return false ; } else { $ loc = & $ loc [ $ step ] ; } } return true ; }
Confirm or deny that an item exists

@param $alias
@return bool
Confirm or deny that an item exists