Further, the changes were made for very good reasons, such as allowing beginners to accept user input on day 1 without opening ACE exploits in their programs, and having plain double-quoted string literals actually produce a string rather than an immutable byte buffer that vaguely assumes a generic code-page encoding, except for the contexts where it will complain if it's not plain ASCII (admittedly, this is still an improvement over trying to handle text in C with only the standard library), and making sure that decoding operations don't produce encoding errors and vice-versa, and making `isinstance(1<<64, int)` give the expected `True` result, and making `except` syntax make sense, and making sure there aren't two fundamentally different kinds of user-defined class.
And by making these changes, we actually got Python 3 in about 2.5 years (4.5 if you allow for the first couple of releases having some issues figuring out the string literal transition and other such details — I agree they were premature) and were able to offer another 11 (9) for everyone to migrate. Whereas with Raku the entire 13.5 (more like 15.5) year period was spent on design and implementation, and now there hasn't been a new stable release for almost 5 years.
Unfortunately, python's developers seem to have demonstrated tremendous contempt for the users of the language, and for existing code bases.
Other languages (though not all.... <cough, swift>) have actual language specifications and standards (that even keep working as runtime systems evolve), and are not so keen on throwing users and their code off a cliff.
Platforms should absorb pain so that their users don't have to, and avoid introducing breaking changes that multiply pain across an entire user base.
Apple (also known for arrogance combined with contempt for their developers) also gets this wrong, and routinely breaks iOS and swift apps every year.
Can you give a concrete example of a problem you encountered while porting 2->3 code caused by a poorly chosen default in 3?
> compatibility features and libraries
You mean like `lib2to3`? Or all the backports 2.7 got, e.g. what's listed at https://wiki.python.org/moin/StandardLibraryBackports ? Or the `__future__` system? Or third-party support like `six` (still immensely popular, though presumably only in CI)?
> the print statement (which could have coexisted with a print() function)
No, it absolutely could not have. Not with the same name, and making the name refer to the function was the point. The print statement syntax was inelegant, quirky and confusing. For example, parentheses can affect the meaning in unusual ways:
$ py2.7 -c 'print (1,); print 2'
(1,)
2
$ py2.7 -c 'print 1,; print 2'
1 2
> python's developers seem to have demonstrated tremendous contempt for the users
I don't understand how you have come to infer such an attitude. Any suspicion that they are introducing breaking changes on a whim will be immediately quashed by reading the discussion behind any of those breaking changes. (Not to mention what happens with the rejected proposals.)
> and avoid introducing breaking changes that multiply pain across an entire user base.
What breaking change was introduced in Python 3.x during your history of using it that caused a nontrivial problem for you? How many years do you believe you were given to account for it?
It could have fairly trivially for the vast majority of use cases (no space between print and parenthesis if you want to call the function) but apparently that would have made some python maintainers unhappy. So it was ripped out and a breaking change was introduced with no recourse (not even, say, from __past__ import print_statement or something).
This is part of what I mean by demonstrating tremendous contempt for the user base and for existing code.