[melling]

Well, the one big reason was that you were going to lose support for Python 2. Guido just took that reason away and now tens of thousands of new Python apps are going to be written in Python 2 because they've got another 6 years to worry about it.

Guido just created a bigger problem. No good deed goes unpunished.

[darkarmani]

> Well, the one big reason was that you were going to lose support for Python 2. Guido just took that reason away and now tens of thousands of new Python apps are going to be written in Python 2 because they've got another 6 years to worry about it.

This shows a serious disconnect from reality. Discontinued support for Python 2 was never a major reason to move to python 3 for apps. Library support is WAY more important in the choice to switch. If all of the libraries worked with Python 3, there would be no reason for app writers not to switch.

[Myrmornis]

Yeah but I understand GP's sentiment. As someone who writes python for my living currently, I'm a little disappointed at this because it's hard to imagine that it doesn't move further into the future the day on which we will switch our code base. I don't need to be a 3-second attention span novelty junkie to just get some pleasure out of using the latest version of the language at my workplace.

[derefr]

It feels like the problem is the black-and-white thinking on the part of developers of every language being either "okay to develop in" or "completely unsupported."

If only there was a way to deprecate a language, with the same meaning as deprecating an API method: "it's not gone yet, but it will be soon, so in strict mode using it is an error." (The main problem to solve would be: strict mode of what? The package manager?)

[al2o3cr]

"If only there was a way to deprecate a language, with the same meaning as deprecating an API method"

One way that usually works is to release a newer version and stop updating the old one after five years. Oh wait...

[derefr]

It's the "using it in strict mode is an error" part that's important. Compilers can automatically refuse to compile deprecated-but-not-broken code. What can automatically refuse to let you start a new project in a deprecated-but-not-broken language?

[Pacabel]

Where exactly do you get this "tens of thousands" number from?

[coldtea]

From the number of Python programmers out there and the percentage using Python 2.

In fact there'd be "tens of thousands" websites made with Python alone (Django et al), so the number of apps in total will be much higher.

Heck, people doing scientific Python are more than 10.000, and they write more than one new apps for their research every year.

[Pacabel]

Oh, I see. Some people here misinterpreted what I wrote to suggest that Python isn't widely used. Clearly that's not what I meant.

I just dislike how melling basically pulled a number out of his ass, and then used it as "evidence" to back up his claims. I wouldn't even consider it a low-quality estimate, since he doesn't even try to justify or explain how that number was obtained.

In this case, "tens of thousands" could very well really be "hundreds of thousands". It could be significantly less, too. Regardless, it's purely speculative. Using such made up numbers makes his argument weaker than perhaps not using any such value at all.

[melling]

No, I picked what I thought would be a lower bound. Do you think it will only be a few hundred or few thousand over 6 years? Python is an extremely popular language.

[Pacabel]

I really do not know. I prefer not to make specific guesses, even lower-bound estimates, when there is insufficient information available.

[melling]

I've worked in industry for 20 years. People take the same version of the interpreter, or start with existing scripts, to create new scripts. Even if there's a one rev difference, people often don't bother to upgrade. There will probably be hundreds of thousands, if not millions of Python 2.x scripts written over the next 6 years. Many will be small, of course, but it's code that will have to be checked against 3.x at some point. I threw out the conservative number because I thought it would be obvious to most people that given Python's popularity, a lot of new 2.x code will be written.

Obviously, if people were moving more quickly there wouldn't be a need to push out 2.7 support until 2020.