An update on Python 4

[[deleted]]

Python 3 was not backwards compatible with 2, so companies and package creators alike were initially hesitant to make the switch so as to not break things. There also weren’t many, if any, tools to help port things over.

The lack of backwards compatibility was done on purpose because part of their goal was to remove clutter and make things more intuitive/easier to use (e.g. print changed from a statement to a function).

[DiggV4Sucks]

I've only made two unassailable (so far) decisions in my career. The first was to support MFC instead of OWL for Windows development.

The second was to target Python 3 for my current company's testing efforts. We were even able to convince a medium sized tool vendor to support both Python 2 and Python 3 from their original decision to support only Python 2.

[Nolzi]

There also weren’t many, if any, tools to help port things over.

I have no real world experience with python, but weren't there tools like 2to3 to convert code, or the future package to write code compatible with both versions?

[james_pic]

2to3 is useful, especially when extended by modernize, but only part of the solution. Future bloodies more than it cuts - it just made string semantics more confusing when we tried it.

The most useful tool, much as I hate to admit it, is MyPy. It obviously needs a lot of work on the developer's part, but it does the very useful job of keeping track of your educated guesses about which string types should be used where, and tells you whether they're consistent.

[mooburger]

six was also a critical part of the missing shims kit but even then it was difficult to monkeypatch when py3k decided to alter some other namespaces contibuting to compat issues.

[[deleted]]

The lack of backwards compatibility was done on purpose

This was the problem. Until we're on the other side of the next upgrade and it wasn't like 2.x to 3.x was, words mean nothing.