[simonh]

I'm not that familiar with Ruby, but fix any of its version updates fundamentally break backwards compatibility the way Python did with the Unicode string changes in 3.0?

My organisation has a massive internal platform, with hundreds of applications all developed in Python 2.6. We are in the process of upgrading the base platform to 2.7 but I believe we will never be able to upgrade to 3.x. We have hundreds of thousands, perhaps millions of lines of Python code and it's growing all the time. When we started the project version 3 wasn't really a practical option.

[dragonwriter]

> I'm not that familiar with Ruby, but fix any of its version updates fundamentally break backwards compatibility the way Python did with the Unicode string changes in 3.0?

Yes, the Ruby 1.9 release broke backward compatibility and there was quite a time when lots of Ruby stuff was stuck on Ruby 1.8 and you saw much the same stuff as Python 2 to Python 3.

Indeed, one of the big issues was a major change in string handling (to encoding-aware strings), just as with Python.

It resolved more quickly, but I think that's largely due to the fact that Ruby had less diversity of libraries that were critical in one domain or another than Python, and thus less holding it back from changing over. Python has been something of a victim of its own success here.