Source mapping (part of ES6) gives proper error messages for other languages compiled into JS, I believe this would include Pyjamas etc.
But do Python programmers who haven't programmed for the browser before realize how important async is?
Tornado and Twisted users are used to passing around functions, but they're very small subsets of the Python community, who, if asked to fetch something and do something with it, would generally wait until it's fetched.
"But do Python programmers who haven't programmed for the browser before realize how important async is?"
Not a very useful question. Anyone who has ever programmed on a GUI of any sort will know how important that is, anybody else will rapidly learn. The vague-but-pervasive idea that web developers invented async about two years ago and thus "async experience" can be presumed to have not penetrated out to those other less enlightened communities who still haven't discovered its Mighty Powers is... not exactly historically accurate, let us say. GUIs have always had to deal with async issues, going all the way back to the dawn of GUIs. It's not a new idea. It's probably older than you are. (It is older than I am.)
> Anyone who has ever programmed on a GUI of any sort
Most Python folks are backend folks. As mentioned, I frequently see Python folk (including myself a few years ago) confusing async code for JS being a complex language.
> anybody else will rapidly learn.
Why?
Delphi and the other desktop app RAD tools took care of callback integration - the entry point for the code was generally not shown, it was just visually attached to the button.
The subsets of people that do UI work right (Qt, Gtk, etc.) and people that do networking right (Twisted) are relatively large. I wouldn't worry about it too much.
But do Python programmers who haven't programmed for the browser before realize how important async is?
Tornado and Twisted users are used to passing around functions, but they're very small subsets of the Python community, who, if asked to fetch something and do something with it, would generally wait until it's fetched.