But why?

[Meant to post this some time ago but forgot LWN has a "confirm" step instead of editing comments]

But do you think ramming through PEP 498 worked out better because this is generally a good way to do things and PEP 572 was just bad luck?

I'm looking back at things like PEP 414 (unicode literals in Python 3 so that more Python 2 code "just works") and I see plenty of effort put into figuring out what's actually objectionable here, let's narrow this down and do just the minimum possible to make the most people happy while annoying as few as possible.

My feeling is that with PEP 498 there was an attempt to shortcut, "I can't be bothered to persuade these people that I'm right, so we'll just do it, and then hopefully they'll come along".

But that's doubly risky, the least awful outcome is that you were right but you alienate loads of people and cause unnecessary strife, which seems to be what Guido thinks happened here. And actually it's also possible that since you insisted on doing it anyway you were wrong, you will eventually _realise_ you were wrong and so either it's going to get reversed out or the language will fade away ("Remember when Python didn't have that stupid assignment bug?").

Again, I bring this up because we're talking about programming languages here. This is not a penalty shoot-out, we have great luxury of time. What would be the negative consequences of PEP 572 taking twelve months, or five years to search for consensus ? Other than those in favour didn't want to wait?