[Python-ideas] A Continuations Compromise in Python

[Greg Ewing]

John Graham wrote:
> True, but similar to ABC's, if each of your major users (i.e.
> frameworks) ends up reinventing a incompatible wheel, when is it time
> to try and come up with some small standard they can all share?

Maybe I'm missing something, but I don't see how a
stateless web server would make use of any kind of
continuation-invoking mechanism.

The main loop of such a server just gets a request,
maps the url to a function, and then calls that
function with parameters from the query string.
The function does its thing and returns some
html to send back to the browser.

It has no idea which function should be called
next, because there's no "next" in a stateless
server -- it depends entirely on what the user
of the browser does from there.

Another way of thinking about this is that the
continuation is encoded in the html form that the
function returns. So the main loop of the server,
together with the browser+user, can be thought of
as a kind of trampoline, where the "function" you
return isn't a Python function at all, but a form
whose "submit" button sends a query that results
in the desired function being called.

It seems to me that the existing Python language
is perfectly adequate for expressing this.

-- 
Greg