def __init__(self, name, host='127.0.0.1', port=27017):
        self.name = name
        self.host = host
        self.port = port
def visitdir(self, dir):
        dir = normalizerootdir(dir, "visitdir")
        if dir == "":
            dir = self._path
        else:
            dir = self._path + "/" + dir
        return self._matcher.visitdir(dir)