Comment by pdonis
2 years ago
It's a fair point that Python minor version changes can and do involve removal of previously deprecated APIs, which would break old code that used those APIs.
That said, when I look through the 3.11 release notes you refer to, I see basically three categories of such changes:
- Items that were deprecated very early in Python 3 development (3.2, for example). Since 3.3 was the first basically usable Python 3 version, I doubt there is much legacy Python 3 code that will be broken by these changes.
- Items related to early versions of new APIs introduced in Python 3 (for example, deprecating early versions of the async APIs now that async development has settled on later ones that were found to work better). These sorts of breaking changes can be avoided by not using APIs that are basically experimental and are declared to be so (as the early async APIs were).
- Items related to supporting old OSs or data formats that nobody really uses any more.
So, while these are, strictly speaking, breaking changes, I still don't think that "constant breaking changes" is a good description of the general state of Python development.
Python's changes between releases are not limited to removing deprecated APIs. Sometimes semantics changes in breaking ways, or new reserved words crop up, etc. etc. It certainly is Russian roulette trying to run python code on any version other than the one it was written for.
> Sometimes semantics changes in breaking ways, or new reserved words crop up, etc. etc.
Examples?
I know this specific example because it was one of a handful of reasons that delayed my workplace from upgrading past Python 3.5 (I think) for quite a while because of the addition of the reserved word `async`.
https://docs.python.org/3.11/whatsnew/3.5.html#pep-492-corou...
Can't speak to what GP was alluding to re: breaking semantic changes.
For me switching to Python 3.11 was really tough because of various legacy stuff removals (like coroutine decorators etc). While my code did not use these, the dependencies did. For some dependencies I had to switch to different libraries altogether - and that required rewriting my code to work with them.
There was also some time in the past when async became a keyword. It turned out many packages had variables named async and that caused quite a bit of pain too.