alt Hacker NewsI suppose so, but I think it's relatively rare for languages to just drop support for older features and force developers to rewrite code using newer mechanisms.
Python 2 to 3 is a good example of what can be expected to happen - very slow adoption of the new version since companies may just not have the resources or desire to rewrite existing code that is running without problems.
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> Python 2 to 3 is a good example of what can be expected to happen
People keep bringing this up when discussing backwards compatibility breaks, but I think the conclusion should be a bit more nuanced than just "backwards compatibility break <=> years (decades?) of pain".
IMHO, the problem was the backwards compatibility break coupled with the inability to use Python 2 code from 3 and vice versa. This meant that not only did you need to migrate your own code, but you also needed everything you depend on to also support Python 3. This applied in reverse as well - if you as a library developer naively upgraded to Python 3, that left your Python 2 consumers behind.
Obviously the migration story got better over time with improvements to 2to3, six, etc., that allowed a single codebase to work under both Python 2 and 3, but I think the big takeaway here is that backwards compatibility breaks can be made much more friendly as long as upgrades can be performed independently of each other.
Python3 drops support for older versions of python3 all the time. Every single release comes with a bunch of deprecated and removed features. There is a very strong chance that a python 3.7 codebase is totally broken on 3.14. Almost no language takes backwards compatibility as seriously as c++ does.
Late in the C++ 20 timeline P1881 Epochs were proposed. Similar to Rust's editions, which at that time had been tried in anger only once (2018 Edition) this proposed that there should be a way for C++ to evolve, forbidding obsolete syntax in newer projects rather than just growing forever like cancer.
Epochs was given the usual WG21 treatment and that's the end of that. Rust shipped 2021 Edition, and 2024 Edition, and I see no reason to think 2027 Edition won't happen.
The current iteration of Bjarne's "Profiles" idea is in a similar ballpark though it got there via a very different route. This time because it will aid safety to outlaw things that are now considered a bad idea. If this goes anywhere its nearest ship vehicle is C++ 29.
Now, Python 2 to Python 3 did take a few years, maybe a decade. But just shipping the mechanism to reform C++ looks likely to take at least nine years. Not the reform, just the mechanism to enable it.