[Python-Dev] Add a frozendict builtin type (original) (raw)

Serhiy Storchaka storchaka at gmail.com
Thu Mar 1 15:17:35 CET 2012

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.

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