Ethan Furman <ethan <at> stoneleaf.us> writes: > On 04/14/2016 12:03 AM, Michael Mysinger via Python-Dev wrote: > > In particular, one RichPath > > class might return bytes and another str, or even worse the same class might > > sometimes return bytes and sometimes str. When will os.path.join blow up due > > to mixing bytes and str and when will it work in those situations? > > What are you asking here? ... Meaning allowing os.fspath() > and __fspath__ to return either bytes or str will never cause the > combination of bytes and str to work. Said another way: if you are > using os.path.join then all the pieces have be str or all the pieces > have to be bytes.
I am saying that if os.path.join now accepts RichPath objects, and those objects can return either str or bytes, then its much harder to reason about when I have all bytes or all strings. In essence, you will force me to pre- wrap all RichPath objects in either os.fsencode(os.fspath(path)) or os.fsdecode(os.fspath(path)), just so I can reason about the type. And if I have to always do that wrapping then os.path.join doesn't need to accept RichPath objects and call fspath at all. _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
