New submission from Scott Sanderson <scout...@gmail.com>:
In some circumstances, it's useful to be able in inspect the parameters with which an instance of functools.lru_cache was instantiated. It's currently possible to recover the cache's maxsize via the .cache_info() method, but there's no way to recover the value passed for `typed`, which controls whether the lru_cache's cache is partitioned by input type. This came up in the context of cloudpickle, a library that tries to extend pickle to support more types (in particular, interactively-defined functions and classes) for use-cases like cluster computing. It's currently not possible to pickle an lru-cache decorated function that's defined in __main__ (which includes, e.g. a Jupyter Notebook). We can **almost** fix this with a pure library solution (see https://github.com/cloudpipe/cloudpickle/pull/309), but we're currently blocked by the fact that there's no way to recover the value that was passed for `typed`. Exposing a .typed attribute on the extension type for lru_cached functions fixes this For more discussion, see the above linked PR, along with https://github.com/cloudpipe/cloudpickle/issues/178. ---------- components: Library (Lib) messages: 355226 nosy: Scott Sanderson2 priority: normal severity: normal status: open title: Expose the value passed of typed passed to functools.lru_cache type: enhancement versions: Python 3.9 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue38565> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
