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0 pointsBuckRogers9y ago0 comments

Those can be built into Grumpy if anyone cares to do so. You don't need Python3 for that stuff. Someone, one developer, recently released a Python 2.8 that backported almost every new Python3 feature.

I'm hoping it becomes a permanent fork of Python2 that uses the Go runtime. That would really be great and exactly what they've got now.

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4 comments · 1 top-level

int_19h9y ago· 3 in thread

If you backport every new Python3 feature to Python2, it becomes Python3, by definition.

BuckRogersOP9y ago

Except that "Python3" would compile and run Python2 source code. So it would be "Python3" but backwards compatible. Which is exactly what everyone wanted (other than a performance boost).

dismantlethesun9y ago

It could become Python 2.8, wherein the standard library has both the legacy versions and the new versions, and any cross-compatible syntax is allowed.

This leaves us with more than 1 way to do things, like meta-class declaration.

There's a lot in Python 3 where changes were made to the syntax for 'clarity', but those worts weren't removed for any technical reason but because of the thought that since backwards compatability was being broken anyways, then we might as well get the most bang for our buck.

int_19h9y ago

> It could become Python 2.8, wherein the standard library has both the legacy versions and the new versions, and any cross-compatible syntax is allowed.

So two `builtin` modules, then?

What if someone does `sys.modules['builtin']`? Or any other kind of explicit string-based lookup?

How does pickle figure out which types to instantiate? There'd be a lot of types with same qualified names but different implementations with this approach...

It feels like the only way this would work reliably, is if you completely isolate the Py2 and Py3 universes. So if you e.g. pickle from Py2 code, it only looks at modules and types that Py2 universe knows, and vice versa.

But then what happens when code using the old library interacts with the new one (e.g. tries to pass objects around)? If that is prohibited, then you effectively still have two different languages, just with a single shared implementation - but no ability to gradually replace bits and pieces of code, for example, which would seem to be the biggest motivation for such a thing.

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