[plt-scheme] continuation barrier

your code do not use "send/suspend"
my code is like your, but "send/suspend" don't work

> If you want sandboxed code to be part of the web server, then you
> should probably write some wrapper that will call a function inside
> the sandbox with the query, and display the result it returned.

I have written sandbox evaluator, which run web functions (parts of my web-application)
But I need "send/suspend" in web functions, and "send/suspend" include continuations in it
and if "send/suspend" appear in such function, raise error:

"call-with-composable-continuation: continuation includes no prompt with the given tag: #<continuation-prompt-tag:servlet>"




18.04.09, 10:54, "Eli Barzilay" <eli at barzilay.org>:

> On Apr 18, DTNOIZR wrote:
> > > This code runs without problems in PLT Scheme 4.1.5
> > I use 4.1.4. because of 4.1.5. have some errors ...
> > 
> > i wanna create web scheme interpreter
> > every user have its own sandbox with its own tweaks
> So you wouldn't want the sandboxed code to be able to interfere with
> your own server -- which is why its environment is isolated.  Below is
> a sample quick web-server based evaluator that I once wrote -- if you
> try it, you'll see that capturing continuations and calling them is
> fine as long as it's user code that calls its own continuations.
> If you want sandboxed code to be part of the web server, then you
> should probably write some wrapper that will call a function inside
> the sandbox with the query, and display the result it returned.  This
> way the continuations that are captured inside the sandbox are kept
> private, and no continuation barriers get in your way.