the Gravity of Python 2

[Steven D'Aprano]

Martijn Faassen wrote:

> I also argue that for those projects to move anywhere, they need a
> clear, blessed, official, as simple as possible, incremental upgrade
> path. That's why I argue for a Python 2.8.

That incremental upgrade path is Python 2.7.

Remember, when Python 3 first came out, the current version of Python was
2.5. 2.6 came out roughly simultaneously with Python 3. So the expected
upgrade path is:


"Bleeding edge" adaptors:
2.5 -> 3.0

Early adaptors:
2.5 -> 2.6 -> 3.1 or 3.2

Slower adaptors:
2.5 -> 2.6 -> 2.7 -> 3.3 or 3.4

Late adaptors:
2.5 -> 2.6 -> 2.7 -> 3.5 (expected to be about 18-24 months)

Laggards who wait until support for 2.7 is dropped:
2.5 -> 2.6 -> 2.7 -> 3.6 or 3.7

Adding 2.8 doesn't help. It just gives people another excuse to delay
migrating. Then, in another two or three years, they'll demand 2.9, and put
it off again. Then they'll insist that 15 years wasn't long enough to
migrate their code, and demand 2.10.

I have no objection to people delaying migrating. There were lots of risks
and difficulties in migrating to 3.1 or 3.2, there are fewer risks and
difficulties in migrating to 3.3 and 3.4, and there will be even fewer by
the time 3.5 and 3.6 come out. People should migrate when they are
comfortable. They may even decide to stick to 2.7 for as long as they can
find a computer capable of running it, security updates or no security
updates. That's all fine.

What's not fine though is people holding the rest of us back with their
negativity and FUD that Python 3 is a mistake.


-- 
Steven