July 2010 - cl-prevalence-devel@lists.common-lisp.net

[cl-prevalence-devel] 2D arrays
by Krzysztof Drewniak 05 Jul '10

05 Jul '10

Is there any major problems with getting 2D arrays (sequences of sequences) serialized? (I'm working on a game and trying to find a serialization libraryt that does what I need) Krzysztof Drewniak -- X-Real-Email-With-Antispam: krzysdrewniak at gmail dot com pgp key on keyserver.ubuntu.com and maybe some other place too

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Re: [cl-prevalence-devel] Patch for serialization of arbitrary data
by Leslie P. Polzer 05 Jul '10

05 Jul '10

Krzysztof Drewniak wrote: > --- src/serialization/xml.lisp.old 2010-06-10 20:50:24.000000000 -0500 > +++ src/serialization/xml.lisp 2010-06-10 21:24:34.000000000 -0500 > @@ -196,6 +196,12 @@ > (write-string "</SLOT>" stream))) > (write-string "</OBJECT>" stream))))) > > +;;anything we don't know about > +(defmethod serialize-xml-internal (object stream serialization-state) > + (declare (ignore serialization-state)) > + (write-string "<ARBITRARY>" stream) > + (print object stream) > + (write-string "</ARBITRARY>" stream)) > > ;;;; DESERIALIZATION > > @@ -283,6 +289,11 @@ > (declare (ignore name attributes parent-seed seed)) > nil)) > > +(defmethod deserialize-xml-finish-element-aux ((name (eql :arbitrary)) > + attributes parent-seed seed) > + (declare (ignore name attributes parent-seed)) > + (read (make-string-input-stream seed))) > + I'm not sure whether this one is good. We're mixing XML and SEXP serialization. Do you have a specific use case? Leslie

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[cl-prevalence-devel] Opening the transaction log - Clozure CL
by William Bruschi 04 Jul '10

04 Jul '10

The Clozure CL implementation has added additional keywords to OPEN, including the :SHARING keyword which controls the access to the stream by multiple threads. The default value is :PRIVATE, which allows access to only the thread that created the stream. More info here: http://openmcl.clozure.com/manual/chapter9.1.html#CCL-Stream-Extensions I was using cl-prevalence as a backend for a Weblocks application when I stumbled upon thread locking errors while accessing the site with multiple browsers. Setting :SHARING to nil fixed my problem. Should this be the default behavior for cl-prevalence? After skimming the code, it appears cl-prevalence has it's own locking mechanisms, making Clozure's extra keyword arguments unnecessary. I also noticed in the TODO file that porting to ccl is on the list. In case anyone is curious, here's how to reproduce the error in Weblocks: 1. Create a new project as outlined in the bottom of http://trac.common-lisp.net/cl-weblocks/wiki/UserManual 2. Edit you init-session.lisp file to this: (defun init-user-session (root) (setf (widget-children root) (list (make-grid-edit)))) (defclass thing () ((id :initform nil :initarg :id :accessor thing-id :type (or null integer)) (name :initform nil :initarg :name :accessor thing-name))) (defun make-grid-edit () (make-instance 'gridedit :data-class 'thing)) 3. Open the site using two different browsers. Add a record using each browser. The second time you add a record, you receive this error: SIMPLE-ERROR: Stream #<BASIC-FILE-CHARACTER-OUTPUT-STREAM ("/<path-to-file>/transaction-log.xml"/15 ISO-8859-1) #x1987FB3E> is private to #<PROCESS Hunchentoot worker (client: 127.0.0.1:47448)(14) [Reset] #x1983AA9E>

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