New submission from Batuhan Taskaya <isidenti...@gmail.com>:
Since strings are immutable types, we could fold some operation on top of them. Serhiy has done some work on issue 28307 regarding folding `str % args` combination, which I think we can extend even further. One simple example that I daily encounter is that, there is this pattern '/'.join([something, something_else, user_arg]) where people would join N number of elements together with a separator, where the N is something that we know. Just a search over some locally cloned PyPI projects (a couple thousand, showed 5000+ occurrences where this optimization applies). The preliminary benchmarks indicate that the speedup is about %40. Though there are multiple issues that might concern others: - type checking, f-strings cast automatically but .join() requires each element to be a string subclass. The current implementation introduces a new conversion called 'c' which actually does the type checking instead of converting the value. - preventing a call to a runtime function, I belive that this work is not that different than issue 28307 which prevents str.__mod__ though I understand the concern Here is the implementation if anybody wants to take a look at it: https://github.com/isidentical/cpython/commit/d7ea8f6e38578ba06d28deb4b4a8df676887ec26 I believe that the implementation can be optimized further (etc if a continuous block of elements are a string, then we can load all of them in one go!). And some cases proved that the f-strings might be faster than the join by 1.7-1.8x. ---------- messages: 394049 nosy: BTaskaya, eric.smith, pablogsal, serhiy.storchaka priority: normal severity: normal status: open title: Folding ''.join(<known number of elts>) into f-strings _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue44194> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
