[racket] distributed places - throwing dcgm-type contract violation on *channel-get

Just to update, also tried this on v5.3.1 using 
spawn-node-supervise-place-at with #:thunk set.  same result.

On 12/14/2012 03:31 PM, Matthew Eric Bassett wrote:
> Hey folks,
>
> I was playing around with distributed places and I ran into a some 
> problems.  I'm using racket v5.3 and am following the docs from the 
> racket reference 
> (http://docs.racket-lang.org/reference/distributed-places.html)
>
> Let's say we have an example just like the one in the reference.
>
> hello-world-place.rkt
> ----------------------
> (define (hello-world)
>     (place ch (printf "hello-world received: ~a\n" (place-channel-get 
> ch))
>     (place-channel-put ch "Hello World\n")
>     (printf "hello-world sent: Hello World\n")))
>
> Then from the racket xrepl we do
>
> >> (define-values (node pl)
>             (spawn-node-supervise-dynamic-place-at remote-node 
> "hello-world-place.rkt" 'hello-world))
> ; there's now a racket process running on my remote-node
> >> (*channel-put pl "hi")
> ; the remote node shuts down as we expect, giving the 
> place-channel-get should have locked it until this point.
> >> (*channel-get pl)
> ; dcgm-type: contract violation
> ;   expected: dcgm?
> ;   given: #<eof>
> ;   context...:
> ; /usr/local/lib/racket/collects/racket/place/distributed.rkt:442:8: loop
> ;    /usr/local/lib/racket/collects/xrepl/xrepl.rkt:1341:0
> ;    /usr/local/lib/racket/collects/racket/private/misc.rkt:87:7
>
> I've tried [naively] using place-channel-put/get instead of 
> *channel-put/get, same result.  Wrapping it in a message-router makes 
> no difference.
>
> >> (message-router node (after-seconds 2 (*channel-put pl "hi!") 
> (*channel-get pl)))
> ; gives same result as above.
>
> Any ideas what I'm doing wrong or what I'm missing?
>
> Many thanks,
>
>


-- 
Matthew Eric Bassett | http://mebassett.info