Prev: A link to a collection of tutorials on LISP.
Next: A link to a collection of tutorials on LISP.
From: Thomas A. Russ on 29 Jun 2010 02:13
"Scott L. Burson" <gyro(a)zeta-soft.com> writes:

> On Jun 27, 4:06��pm, Peter Keller <psil...(a)cs.wisc.edu> wrote:
> > In my case, I've implemented a master/worker paradigm with distributed
> > processes. The master process packs up the worker's task data along with the
> > symbol associated with the function on the worker side and sends it to the
> > worker process in an RPC-like model. I use cl-serializer, so I actually do send
> > the target function's symbol to the client side, which arrives uninterned--it
> > could just have easily been the string of the function's name though.
>
> I haven't used cl-serializer, but I would suggest it is standard
> practice for a serializer to preserve the package of a serialized
> symbol.

I haven't used cl-serializer either, but taking some time to look at the
code shows that it does, as expected, preserve the package when a symbol
is serialized. The code itself (written with some other funky macros, I
guess) is this:

(def serializer-deserializer symbol +symbol-code+ symbol
(progn
(write-generic-string (symbol-name object) context)
(serialize-package (symbol-package object) context))
(announce-identity (intern (read-generic-string context)
(deserialize-package context)) context))

So, when serializing, it most certainly preserves both the symbol-name
and the symbol-package. And it uses the package when deserializing as
well.

The only symbols that are sent over uninterned are symbols that are
uninterned on the sending side.

Now I recall Peter mentioning MAKE-SYMBOL at some point up-thread. If
that is how he is creating symbols, then he is getting uninterned
symbols which will not generally be serializable with identity in any
case. I didn't see if there was anything that tried to keep at least
some identity going, but using MAKE-SYMBOL to name anything that you
want to be able to reference again by name is a bad idea(tm).

So, cl-serializer is clearly NOT the problem with losing symbol
identity. There must be some other problem like using uninterned
symbols in the first place. I suspect MAKE-SYMBOL may be at the root of
the problem.

--
Thomas A. Russ, USC/Information Sciences Institute
First  |  Prev  | 
Pages: 1 2 3 4 5 6 7
Prev: A link to a collection of tutorials on LISP.
Next: A link to a collection of tutorials on LISP.