March 1, 2012
2:17 p.m.
01.03.12 11:29, André Malo написав(ла):
- Caching. My data container objects (say, resultsets from a db or something) usually inherit from list or dict (sometimes also set) and are cached heavily. In order to ensure that they are not modified (accidentially), I have to choices: deepcopy or immutability. deepcopy is so expensive, that it's often cheaper to just leave out the cache. So I use immutability. (oh well, the objects are further restricted with __slots__)
This is the first rational use of frozendict that I see. However, a deep copy is still necessary to create the frozendict. For this case, I believe, would be better to "freeze" dict inplace and then copy-on-write it.