Earlier quoted context omitted.
I don’t use Julia but those language changes would have me worried that existing code would start behaving differently because of parser changes.
We're very careful with changes and give thorough deprecation warnings. When you upgrade and the meaning of something that you're using is going to change in the following version, you will get a warning to change it now, with specific detail of the new spelling of that feature. So as long as you don't skip major versions, you're safe. Corollary: don't skip major versions. Even if you're upgrading from 0.4 to 0.7, yo…
That seems reasonable, and it’s what Django does as well I think. The change list doesn’t mention it hence my comment.
I’m not surprised that deprecation logic is harder than the new features.