Today I wrote some example code for trying out `serial-lambda` from
`(require web-server/lang/serial-lambda)`. Here is what I currently have:

#lang racket

(require web-server/lang/serial-lambda)
(require racket/serialize)

(define to-send (serial-lambda (x) (* x x)))
(define to-send-2
  (serial-lambda (place-id data)
                 (list 'result
                       (for/list ([i (range 1000)]
                                  [elem (in-cycle data)])
                         (* i elem)))))
(define to-send-3
  (serial-lambda (place-id data custom-proc)
                 (list 'result
                        (for*/list ([i (range 1000)]
                                   [elem data])
                          (* i elem))))))

(define (custom-proc lst)
  (map (λ (x) (* 2 x))

(to-send 4)

(fprintf (current-output-port)
         "Serialized lambda:~a~n"
         (serialize to-send))
(fprintf (current-output-port)
         "Deserialized Serialized lambda: ~a~n"
         (deserialize (serialize to-send)))
(fprintf (current-output-port)
         "Deserialized Serialized lambda of 4: ~a~n"
         ((deserialize (serialize to-send)) 4))

(fprintf (current-output-port)
         "Deserialized Serialized lambda of 4: ~a~n"
         ((deserialize (serialize to-send-2)) 3 '(0 1 2 3)))

(fprintf (current-output-port)
         "lenght Deserialized Serialized lambda of 4: ~a~n"
         (length (caddr ((deserialize (serialize to-send-2)) 3 '(0 1 2

(fprintf (current-output-port)
         "lenght Deserialized Serialized lambda of 4: ~a~n"
         ((deserialize (serialize to-send-3)) 3 '(0 1 2 3) custom-proc))
(fprintf (current-output-port)
         "lenght Deserialized Serialized lambda of 4: ~a~n"
           ((deserialize (serialize to-send-3)) 3 '(0 1 2 3) custom-proc))))

Which I can simply run with `racket serial-lambda-example.rkt`. Some
time ago I started a project called "work-distributor"
(, which I want to
be usable in a way, that users can simply give some lambda to the
distributor and some data, so that the distributor then creates as many
places as specified and distributes the data and lambda to these places.
Then the places should apply the lambda to their portion of the data and
return the results, which the work distributor would merge and return to
the user / caller.
So far the theory.

As it turns out I cannot send lambdas on place channels
so the first issue is, that I have to use an import
(require web-server/lang/serial-lambda)to use something from a
completely unrelated package, in order to get a lambda, which can be
serialized and then send that on the place channel. That would not be so
bad, if it was constrained to that one usage, when the user builds their
lambda, which is going to be given to the work distributor, so that the
work distributor can go on and send it to places.
In a user program however, such serial-lambda seems to be "infectious":

- What if in that serial-lambda the user needs to use some custom
procedure? Does that suddenly also have to be serializable? What about
its "dependencies"? --> everything in the user program ends up being a
serial-lambda. That would be really bad.
- OK, lets say the procedure is visible from the places ... I cannot
seriously require the user of the work distributor to go into the code
of the work distributor and add custom procedures there. That would be
like requiring them to write custom parallelization code.

Maybe I am missing something simple in this whole line of thought.

- Is there a better way than requiring everything to be serial-lambda?
- Is there a better way than requiring the user to edit the work
distributor code to make custom procedures available to the places?
- Is the idea to have lambdas be serializable by default language wide
insane? It would be great to be able to simply start a new place and
give it some arbitrary lambda to execute.

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