New submission from Steele Farnsworth <swfarnswo...@gmail.com>:
I have implemented a class in the C code of the collections module which has similar behavior to the defaultdict class. This class, dynamicdict, supplies values for keys that have not yet been added using a default factory callable, but unlike defaultdict, the missing key itself is passed to the callable. This code can be seen here: https://github.com/swfarnsworth/cpython/blob/3.8/Modules/_collectionsmodule.c#L2234 While this does introduce a lot of redundant code, I'm not sure how it could be done without copying the implementation of the defaultdict class and adjusting how the default factory is called. For example, I don't believe that it's possible to support both behaviors within the defaultdict class without breaking backwards compatibility or adding another parameter to the constructor for the defaultdict class. I would be happy to further explain the concept, implementation, potential use cases, or anything else that might work towards the adoption of this feature. ---------- components: ctypes messages: 366157 nosy: Steele Farnsworth priority: normal severity: normal status: open title: Proposed class for collections: dynamicdict type: enhancement versions: Python 3.9 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue40248> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
