Continuations Based Web Framework - Seaside.

Steve Holden steve at
Sun Jan 2 10:03:10 EST 2005

gabriele renzi wrote:

> Mike Thompson ha scritto:
>> 'Seaside' is a Smalltalk framework for what might be called "Modal Web 
>> Development" or "Synchronous Web Programming", or even "Continuation 
>> Based Web Apps".
>> Very sexy it looks too.  And it seems to be generating a lot of 
>> interest - Ruby and Java variants have already sprung up:
> actually, there are also implementations in Scheme, Common Lisp 
> (UnCommonWeb) and Cocoon-FLOW has similar concepts.
>  And somewhere (I think on the portland pattern repository) I recall 
> reading that Viaweb (aka "the first web app") was written in CPS. Also 
> notice that the Wee project in ruby is more advanced that Borges.
>> I googled for the python spin-off but didn't find one. Closest I found 
>> was Imposter ( which looks 
>> like an earlier, partially failed attempt to do what Seaside now seems 
>> to be delivering.
> I think "independent" more than earlier, it seem many people are 
> reinventing this from time to time.
> Anyway, I just wanted to point out that IIRC something on this lines 
> appeared recently in the nevow svn tree, maybe you can take a look.

I did actually do some sort-of-related work in this area, which I 
presented at PyCon DC 2004 - you can access the paper at

An audience member mentioned the Smalltalk and Scheme-based work on web 
continuation frameworks, and I was sorry my answer at the time seemed 
unduly dismissive. There are some interesting similarities, and though 
my own implementation is decidedly clunky I like to think the paper 
explains some of the advantages of maintaining state and why the "back" 
button is an obnoxious anachronism :-)

Steve Holden     
Python Web Programming
Holden Web LLC      +1 703 861 4237  +1 800 494 3119

More information about the Python-list mailing list