For a quick example (without places), if you enter this in the definitions
window of Dr. Racket:
> #lang racket
> (require web-server/lang/serial-lambda
> racket/serialize
> )
> (define serialized-proc
> (serialize (serial-lambda (x)
> (printf "Your number is: ~a" x))))
> serialized-proc
> ((deserialize serialized-proc) 42)
This is what you will get when you run the program:
> '((3) 1 (('anonymous-module . "lifted.3")) 0 () () (0))
> Your number is: 42
There are a few caveats with serial-lambda. A big one is that you can't use
it in the REPL: it has to be in a module context, so that there's a way to
use the serialization information later. A second caveat is that any
lexical values in the closure of serial-lambda must themselves be
serializable: this is an instance of the general rule that, for serialize
to succeed, all the nested contents of the data structure to be serialized
must be serializable, not just the outermost container. Here's an example:
#lang racket
> (require web-server/lang/serial-lambda
> racket/serialize)
> (define (make-proc lexical-value)
> (serial-lambda (immediate-arg)
> (printf (string-append "This value is part of the closure, so \n"
> "it must be serializable:\n\t ~a\n")
> lexical-value)
> (printf "The immediate argument can be anything:\n\t ~a\n"
> immediate-arg)))
> (struct opaque ())
> (define works
> (make-proc (list 'apples 'peaches 'pears)))
> ;; calling works on an non-serializable argument succeeds
> (works (opaque))
> ;; you can see that the lexical arg shows up
> ;; in the serialized representation
> (serialize works)
> (newline)
> (define broken
> (make-proc (opaque)))
> ;; make-proc will succeed, and broken
> ;; will appear to work as expected
> (broken 42)
> ;; however, attempting to serialize broken
> ;; will raise an exn:fail
> (serialize broken)
If you have specific questions, I am happy to try to help!
-Philip
On Mon, Jan 16, 2017 at 11:13 PM, Andreas Olsson <photoguy....@gmail.com>
wrote:
> Strangely I can't get the example working from the docs and serial lambda
> isn't a cakewalk ether. So if you got a working example please share it!
>
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