[racket] send/suspend outside #lang web-server

There are two send/suspend functions in the Web server collection.

The one from web-server/lang/web is the stateless one. This relies on
the program transformation that #lang web-server implements, so it
must be used inside modules that use that language.

The one from web-server/servlet/web is the stateful one. This is
implemented purely with native continuations, so it can be used
anywhere.

Jay

On Mon, Sep 5, 2011 at 12:44 AM, Veer <diggerrrrr at gmail.com> wrote:
> Can I use send/suspend  outside the #lang web-server module ?
> For example , the two modules  below don't work , I get something like :
> "Attempt to capture a continuation from within an unsafe context: ...."
>
> For statefull servlets this type of example works fine.
>
>
> "Module test.rkt"
> #lang web-server
> (require web-server/servlet-env)
> (require "something.rkt")
>
>
> (define (start request)
>  (show request))
>
> (define (show request)
>
>  (define (gen-resp make-url)
>    (response/xexpr
>     `(html (body (h1 "testing")
>                  (a ((href ,(make-url do-something))) "do something")))))
>
>  (define (do-something request)
>
>    (define something (get-something))
>
>
>    (cond
>      [(request? something) (error 'no-good)]
>      [else (error 'ok "~a" something)]))
>
>  (send/suspend/dispatch gen-resp))
>
> (serve/servlet  start #:stateless? #t )
>
>
> "Module something.rkt"
> #lang racket
> (require web-server/lang/web)
> (require web-server/http/xexpr)
>
> (provide get-something)
>
> (define (get-something)
>
>  (define  req
>    (send/suspend
>     (lambda (make-url)
>       (response/xexpr
>        `(html (body (h1 "something")
>                     (a ((href ,make-url)) "try something")))))))
>
>  (printf "why are we not here\n")
>  'something)
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-- 
Jay McCarthy <jay at cs.byu.edu>
Assistant Professor / Brigham Young University
http://faculty.cs.byu.edu/~jay

"The glory of God is Intelligence" - D&C 93