undefined | Better HN

0 pointsCydeWeys6y ago0 comments

Yup. I like Python3, it's better than 2, and has lots of good new features, but so many of them could simply have been added onto 2 without requiring this huge painstaking migration that cost an unbelievable amount of effort worldwide.

Contrast with Java, which has made much more substantial changes to the language over all these years, but goes to great pains to support backwards compatibility. Upgrading major Java versions was never remotely as painful, and as a result, huge amounts of engineering time was saved.

0 comments

3 comments · 1 top-level

takeda6y ago· 2 in thread

Python 3 features in Python 2 was entire purpose of Python 2.7. All features it came with were backports of python 3 features. They could continue doing that, but then we would never fix the Unicode.

There's so much whining, when they gave over 5 years to do the migration. I think the whole problem was that they gave too much time, and people were thinking it will be like that forever.

Also, Java is not a dynamic language, the type system allows for easy fix of issues like these, the python solution to do that is mypy, but it requires work by adding types.

philwelch6y ago

> There's so much whining, when they gave over 5 years to do the migration.

You make it sound so generous of the Python maintainers to "give over five years" before breaking backwards compatibility--something that C, Java, JavaScript, C++, and probably most other languages haven't done for decades, or in some cases ever. Programming languages are serious basic infrastructure, programmer time is valuable, and Python's installed base is large enough that many man-centuries were probably wasted on this migration.

If the Python maintainers had not given as much time as they did, I doubt the Python community or ecosystem would have transitioned any more quickly than they did. More likely would have been some fork or alternate implementation of Python 2 becoming the new standard.

kerkeslager6y ago

Okay, but how many man-centuries have we spent fixing buffer overflows in C because the type system can't check that without breaking reverse compatibility?

Reverse compatibility isn't free.

3 more replies

j / k navigate · click thread line to collapse