Messenger/Data Transfer Object
The Messenger or Data Transfer Object is a way to pass a clump of information around. The most typical place for this is in return values from functions, where tuples or dictionaries are often used. However, those rely on indexing; in the case of tuples this requires the consumer to keep track of numerical order, and in the case of a dict you must use the d["name"] syntax which can be slightly less desireable.
A Messenger is simply an object with attributes corresponding to the names of the data you want to pass around or return:
# Messenger/MessengerIdiom.py class Messenger: def __init__(self, **kwargs): self.__dict__ = kwargs m = Messenger(info="some information", b=['a', 'list']) m.more = 11 print m.info, m.b, m.more
The trick here is that the __dict__ for the object is just assigned to the dict that is automatically created by the **kwargs argument.
Although one could easily create a Messenger class and put it into a library and import it, there are so few lines to describe it that it usually makes more sense to just define it in-place whenever you need it -- it is probably easier for the reader to follow, as well.