- cl-prevalence-cvs@common-lisp.net - mailman3.common-lisp.net

[cl-prevalence-cvs] CVS update: cl-prevalence/src/package.lisp cl-prevalence/src/prevalence.lisp cl-prevalence/src/serialization.lisp
by Sven Van Caekenberghe 04 Oct '04

04 Oct '04

Update of /project/cl-prevalence/cvsroot/cl-prevalence/src In directory common-lisp.net:/tmp/cvs-serv20795/src Modified Files: package.lisp prevalence.lisp serialization.lisp Log Message: added reset-class-slots Date: Mon Oct 4 16:25:13 2004 Author: scaekenberghe Index: cl-prevalence/src/package.lisp diff -u cl-prevalence/src/package.lisp:1.4 cl-prevalence/src/package.lisp:1.5 --- cl-prevalence/src/package.lisp:1.4 Mon Jun 28 13:57:30 2004 +++ cl-prevalence/src/package.lisp Mon Oct 4 16:25:13 2004 @@ -1,6 +1,6 @@ ;;;; -*- Mode: LISP -*- ;;;; -;;;; $Id: package.lisp,v 1.4 2004/06/28 11:57:30 scaekenberghe Exp $ +;;;; $Id: package.lisp,v 1.5 2004/10/04 14:25:13 scaekenberghe Exp $ ;;;; ;;;; Package definitions for the CL-PREVALENCE project ;;;; @@ -16,7 +16,8 @@ #:serializable-slots #:serialize-xml #:serialize-sexp #:deserialize-xml #:deserialize-sexp - #:make-serialization-state) + #:make-serialization-state + #:reset-known-slots) (:documentation "XML and s-expression based serialization for Common Lisp and CLOS")) (defpackage :cl-prevalence Index: cl-prevalence/src/prevalence.lisp diff -u cl-prevalence/src/prevalence.lisp:1.6 cl-prevalence/src/prevalence.lisp:1.7 --- cl-prevalence/src/prevalence.lisp:1.6 Tue Jul 13 12:30:28 2004 +++ cl-prevalence/src/prevalence.lisp Mon Oct 4 16:25:13 2004 @@ -1,6 +1,6 @@ ;;;; -*- mode: Lisp -*- ;;;; -;;;; $Id: prevalence.lisp,v 1.6 2004/07/13 10:30:28 scaekenberghe Exp $ +;;;; $Id: prevalence.lisp,v 1.7 2004/10/04 14:25:13 scaekenberghe Exp $ ;;;; ;;;; Object Prevalence in Common Lisp ;;;; @@ -367,6 +367,11 @@ (write-sequence buffer out :end read-count) (when (< read-count 4096) (return))))))) +;;; from the serialization package + +(defmethod reset-known-slots ((system prevalence-system) &optional class) + (reset-known-slots (get-serialization-state system) class)) + ;;; extra documentation (setf (documentation 'get-guard 'function) "Access the guard function of a sytem") Index: cl-prevalence/src/serialization.lisp diff -u cl-prevalence/src/serialization.lisp:1.3 cl-prevalence/src/serialization.lisp:1.4 --- cl-prevalence/src/serialization.lisp:1.3 Mon Oct 4 15:45:56 2004 +++ cl-prevalence/src/serialization.lisp Mon Oct 4 16:25:13 2004 @@ -1,6 +1,6 @@ ;;;; -*- mode: Lisp -*- ;;;; -;;;; $Id: serialization.lisp,v 1.3 2004/10/04 13:45:56 scaekenberghe Exp $ +;;;; $Id: serialization.lisp,v 1.4 2004/10/04 14:25:13 scaekenberghe Exp $ ;;;; ;;;; XML and S-Expression based Serialization for Common Lisp and CLOS ;;;; @@ -52,6 +52,9 @@ "Create a reusable serialization state to pass as optional argument to [de]serialize-xml" (make-instance 'serialization-state)) +(defgeneric reset-known-slots (serialization-state &optional class) + (:documentation "Clear the caching of known slots for class, or for all classes if class is nil")) + ;;; Implementation ;; State and Support @@ -74,6 +77,12 @@ (with-slots (hashtable counter) serialization-state (clrhash hashtable) (setf counter 0))) + +(defmethod reset-known-slots ((serialization-state serialization-state) &optional class) + (with-slots (known-slots) serialization-state + (if class + (remhash (if (symbolp class) class (class-name class)) known-slots) + (clrhash known-slots)))) (defmethod known-object-id ((serialization-state serialization-state) object) (gethash object (get-hashtable serialization-state)))

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[cl-prevalence-cvs] CVS update: cl-prevalence/src/serialization.lisp
by Sven Van Caekenberghe 04 Oct '04

04 Oct '04

Update of /project/cl-prevalence/cvsroot/cl-prevalence/src In directory common-lisp.net:/tmp/cvs-serv17983/src Modified Files: serialization.lisp Log Message: bugfix: serialization of an empty string is <string></string> but deserialization of that XML construct was NIL which is not a string we now return an empty string in that case thanks to randall randall Date: Mon Oct 4 15:45:57 2004 Author: scaekenberghe Index: cl-prevalence/src/serialization.lisp diff -u cl-prevalence/src/serialization.lisp:1.2 cl-prevalence/src/serialization.lisp:1.3 --- cl-prevalence/src/serialization.lisp:1.2 Tue Jun 22 10:37:23 2004 +++ cl-prevalence/src/serialization.lisp Mon Oct 4 15:45:56 2004 @@ -1,6 +1,6 @@ ;;;; -*- mode: Lisp -*- ;;;; -;;;; $Id: serialization.lisp,v 1.2 2004/06/22 08:37:23 scaekenberghe Exp $ +;;;; $Id: serialization.lisp,v 1.3 2004/10/04 13:45:56 scaekenberghe Exp $ ;;;; ;;;; XML and S-Expression based Serialization for Common Lisp and CLOS ;;;; @@ -435,7 +435,7 @@ ((:float :ratio :complex :symbol) (read-from-string seed)) (:null nil) (:true t) - (:string seed) + (:string (or seed "")) (:key (car seed)) (:value (car seed)) (:entry (nreverse seed))

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[cl-prevalence-cvs] CVS update: cl-prevalence/src/prevalence.lisp
by Sven Van Caekenberghe 13 Jul '04

13 Jul '04

Update of /project/cl-prevalence/cvsroot/cl-prevalence/src In directory common-lisp.net:/tmp/cvs-serv5940/src Modified Files: prevalence.lisp Log Message: snapshot & backup were broken (thanks to eric blood) Date: Tue Jul 13 03:30:28 2004 Author: scaekenberghe Index: cl-prevalence/src/prevalence.lisp diff -u cl-prevalence/src/prevalence.lisp:1.5 cl-prevalence/src/prevalence.lisp:1.6 --- cl-prevalence/src/prevalence.lisp:1.5 Mon Jun 28 04:56:35 2004 +++ cl-prevalence/src/prevalence.lisp Tue Jul 13 03:30:28 2004 @@ -1,6 +1,6 @@ ;;;; -*- mode: Lisp -*- ;;;; -;;;; $Id: prevalence.lisp,v 1.5 2004/06/28 11:56:35 scaekenberghe Exp $ +;;;; $Id: prevalence.lisp,v 1.6 2004/07/13 10:30:28 scaekenberghe Exp $ ;;;; ;;;; Object Prevalence in Common Lisp ;;;; @@ -238,14 +238,14 @@ (snapshot (get-snapshot system))) (close-open-streams system) (when (probe-file snapshot) - (copy-file snapshot (merge-pathnames (make-pathname :name (get-snapshot-filename timetag) + (copy-file snapshot (merge-pathnames (make-pathname :name (get-snapshot-filename system timetag) :type (get-file-extension system)) snapshot))) (with-open-file (out snapshot :direction :output :if-does-not-exist :create :if-exists :supersede) (funcall (get-serializer system) (get-root-objects system) out (get-serialization-state system))) (when (probe-file transaction-log) - (copy-file transaction-log (merge-pathnames (make-pathname :name (get-transaction-log-filename timetag) + (copy-file transaction-log (merge-pathnames (make-pathname :name (get-transaction-log-filename system timetag) :type (get-file-extension system)) transaction-log)) (delete-file transaction-log)))) @@ -255,10 +255,10 @@ (let* ((timetag (timetag)) (transaction-log (get-transaction-log system)) (snapshot (get-snapshot system)) - (transaction-log-backup (merge-pathnames (make-pathname :name (get-transaction-log-filename timetag) + (transaction-log-backup (merge-pathnames (make-pathname :name (get-transaction-log-filename system timetag) :type (get-file-extension system)) (or directory transaction-log))) - (snapshot-backup (merge-pathnames (make-pathname :name (get-snapshot-filename timetag) + (snapshot-backup (merge-pathnames (make-pathname :name (get-snapshot-filename system timetag) :type (get-file-extension system)) (or directory snapshot)))) (close-open-streams system)

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[cl-prevalence-cvs] CVS update: public_html/index.html
by Sven Van Caekenberghe 08 Jul '04

08 Jul '04

Update of /project/cl-prevalence/cvsroot/public_html In directory common-lisp.net:/tmp/cvs-serv10850 Modified Files: index.html Log Message: added some personal info as well as a reference to a paper Date: Thu Jul 8 12:59:14 2004 Author: scaekenberghe Index: public_html/index.html diff -u public_html/index.html:1.5 public_html/index.html:1.6 --- public_html/index.html:1.5 Thu Jun 24 00:23:40 2004 +++ public_html/index.html Thu Jul 8 12:59:14 2004 @@ -13,10 +13,23 @@ <h1>CL-PREVALENCE</h1> </div> - <p>CL-PREVALENCE is an implementation of <a href="http://www.prevayler.org">Object Prevalence</a> for Common Lisp.</p> + <p> + CL-PREVALENCE is an implementation of <a href="http://www.prevayler.org">Object Prevalence</a> for Common Lisp. + It was written by and is being maintained by <a href="http://homepage.mac.com/svc">Sven Van Caekenberghe</a>. + CL-PREVALENCE is using <a href="http://common-lisp.net/project/s-xml">S-XML</a> for the XML serialization + protocol (there is also a more Lisp-like s-expression-based serialization protocol). + </p> <p> - Object Prevalence is a simple but interesting concept first proposed by Klaus Wuestefeld in 2001. IBM developerWorks has a reasonable <a href="http://www-106.ibm.com/developerworks/library/wa-objprev/">Introduction to Object Prevalence</a> article. The main Java implementation is called <a href="http://www.prevayler.org">Prevayler</a>, with a (chaotic) wiki site with lots of information and discussions. Basically, the idea is this: + Object Prevalence is a simple but interesting concept first proposed by Klaus Wuestefeld in 2001. + IBM developerWorks has a reasonable + <a href="http://www-106.ibm.com/developerworks/library/wa-objprev/">Introduction to Object Prevalence</a> article. + The main Java implementation is called <a href="http://www.prevayler.org">Prevayler</a>, + with a (chaotic) wiki site with lots of information and discussions. + The following academic paper seems to describe the most essential features of Object Prevalence, without naming it as such: + <a href="http://birrell.org/andrew/papers/024-DatabasesPaper.pdf">A Simple and Efficient Implementation for Small Databases</a> + by Birrell, Jones, and Wobber [1987]. + Basically, the idea is this: </p> <ul> <li>Most databases are only a couple of hundreds of megabytes big, often even less.</li> @@ -53,7 +66,8 @@ <p> You can download the LLGPL source code and documentation as <a href="cl-prevalence.tgz">cl-prevalence.tgz</a> - (signature: <a href="cl-prevalence.tgz.asc">cl-prevalence.tgz.asc</a>) + (signature: <a href="cl-prevalence.tgz.asc">cl-prevalence.tgz.asc</a> for which the public key can be found + in the <a href="http://common-lisp.net/keyring.asc">common-lisp.net keyring</a>) (build and/or install with ASDF). There is also <a href="http://common-lisp.net/cgi-bin/viewcvs.cgi/?cvsroot=cl-prevalence">CVS</a> access. </p> @@ -81,7 +95,7 @@ <li><a href="http://common-lisp.net/mailman/listinfo/cl-prevalence-announce">CL-PREVALENCE-ANNOUNCE mailing list info</a></li> </ul> - <p>CVS version $Id: index.html,v 1.5 2004/06/24 07:23:40 scaekenberghe Exp $</p> + <p>CVS version $Id: index.html,v 1.6 2004/07/08 19:59:14 scaekenberghe Exp $</p> <div class="footer"> <p>Back to <a href="http://common-lisp.net/">Common-lisp.net</a>.</p>

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[cl-prevalence-cvs] CVS update: cl-prevalence/src/debug-prevalence.lisp
by Sven Van Caekenberghe 05 Jul '04

05 Jul '04

Update of /project/cl-prevalence/cvsroot/cl-prevalence/src In directory common-lisp.net:/tmp/cvs-serv577/src Modified Files: debug-prevalence.lisp Log Message: forgot to follow a refactoring Date: Mon Jul 5 14:22:08 2004 Author: scaekenberghe Index: cl-prevalence/src/debug-prevalence.lisp diff -u cl-prevalence/src/debug-prevalence.lisp:1.1.1.1 cl-prevalence/src/debug-prevalence.lisp:1.2 --- cl-prevalence/src/debug-prevalence.lisp:1.1.1.1 Sun Jun 20 12:13:38 2004 +++ cl-prevalence/src/debug-prevalence.lisp Mon Jul 5 14:22:08 2004 @@ -1,6 +1,6 @@ ;;;; -*- Mode: LISP -*- ;;;; -;;;; $Id: debug-prevalence.lisp,v 1.1.1.1 2004/06/20 19:13:38 scaekenberghe Exp $ +;;;; $Id: debug-prevalence.lisp,v 1.2 2004/07/05 21:22:08 scaekenberghe Exp $ ;;;; ;;;; Some debugging routines for CL-PREVALENCE ;;;; @@ -24,7 +24,7 @@ "Print the transaction objects making up the transaction log of system to t" (with-open-file (in (get-transaction-log system) :direction :input) (loop - (let ((transaction (deserialize-xml in *serialization-state*))) + (let ((transaction (deserialize-xml in (get-serialization-state system)))) (if (null transaction) (return) (format t "~a~%" transaction))))) @@ -41,7 +41,7 @@ (let (transactions) (with-open-file (in (get-transaction-log system) :direction :input) (loop - (let ((transaction (deserialize-xml in *serialization-state*))) + (let ((transaction (deserialize-xml in (get-serialization-state system)))) (if (null transaction) (return) (push transaction transactions)))))

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[cl-prevalence-cvs] CVS update: cl-prevalence/src/blob.lisp
by Sven Van Caekenberghe 28 Jun '04

28 Jun '04

Update of /project/cl-prevalence/cvsroot/cl-prevalence/src In directory common-lisp.net:/tmp/cvs-serv12352/src Modified Files: blob.lisp Log Message: minor bugfix Date: Mon Jun 28 05:54:47 2004 Author: scaekenberghe Index: cl-prevalence/src/blob.lisp diff -u cl-prevalence/src/blob.lisp:1.1.1.1 cl-prevalence/src/blob.lisp:1.2 --- cl-prevalence/src/blob.lisp:1.1.1.1 Sun Jun 20 12:13:38 2004 +++ cl-prevalence/src/blob.lisp Mon Jun 28 05:54:47 2004 @@ -1,6 +1,6 @@ ;;;; -*- Mode: LISP -*- ;;;; -;;;; $Id: blob.lisp,v 1.1.1.1 2004/06/20 19:13:38 scaekenberghe Exp $ +;;;; $Id: blob.lisp,v 1.2 2004/06/28 12:54:47 scaekenberghe Exp $ ;;;; ;;;; Blobs represent collections of bytes of a certain mime type, ;;;; where the bytes themselves are stored automatically in an ordinary file. @@ -78,7 +78,7 @@ (with-open-file (out (get-file blob) :direction :output :element-type '(unsigned-byte 8) - :if-exists :overwrite + :if-exists :supersede :if-does-not-exist :create) (copy-stream binary-input-stream out)))

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[cl-prevalence-cvs] CVS update: cl-prevalence/test/test-master-slave.lisp
by Sven Van Caekenberghe 28 Jun '04

28 Jun '04

Update of /project/cl-prevalence/cvsroot/cl-prevalence/test In directory common-lisp.net:/tmp/cvs-serv19488/test Added Files: test-master-slave.lisp Log Message: added first proof-of-concept version of master-slave replication between 2 systems Date: Mon Jun 28 04:57:30 2004 Author: scaekenberghe

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[cl-prevalence-cvs] CVS update: cl-prevalence/src/master-slave.lisp cl-prevalence/src/package.lisp
by Sven Van Caekenberghe 28 Jun '04

28 Jun '04

Update of /project/cl-prevalence/cvsroot/cl-prevalence/src In directory common-lisp.net:/tmp/cvs-serv19488/src Modified Files: package.lisp Added Files: master-slave.lisp Log Message: added first proof-of-concept version of master-slave replication between 2 systems Date: Mon Jun 28 04:57:30 2004 Author: scaekenberghe Index: cl-prevalence/src/package.lisp diff -u cl-prevalence/src/package.lisp:1.3 cl-prevalence/src/package.lisp:1.4 --- cl-prevalence/src/package.lisp:1.3 Mon Jun 21 08:26:21 2004 +++ cl-prevalence/src/package.lisp Mon Jun 28 04:57:30 2004 @@ -1,6 +1,6 @@ ;;;; -*- Mode: LISP -*- ;;;; -;;;; $Id: package.lisp,v 1.3 2004/06/21 15:26:21 scaekenberghe Exp $ +;;;; $Id: package.lisp,v 1.4 2004/06/28 11:57:30 scaekenberghe Exp $ ;;;; ;;;; Package definitions for the CL-PREVALENCE project ;;;; @@ -21,7 +21,7 @@ (defpackage :cl-prevalence (:use :cl :s-serialization) - #+NIL(:nicknames :clp) + #+nil (:nicknames :clp) (:export #:make-prevalence-system #:make-transaction @@ -72,7 +72,12 @@ #:tx-change-object-slots #:get-preference #:all-preferences-keys - #:tx-set-preference) + #:tx-set-preference + + #:start-master-client + #:stop-master-client + #:start-slave-server + #:stop-slave-server) (:documentation "An implementation of Object Prevalence for Common Lisp")) ;;;; eof

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[cl-prevalence-cvs] CVS update: cl-prevalence/cl-prevalence.asd
by Sven Van Caekenberghe 28 Jun '04

28 Jun '04

Update of /project/cl-prevalence/cvsroot/cl-prevalence In directory common-lisp.net:/tmp/cvs-serv19488 Modified Files: cl-prevalence.asd Log Message: added first proof-of-concept version of master-slave replication between 2 systems Date: Mon Jun 28 04:57:26 2004 Author: scaekenberghe Index: cl-prevalence/cl-prevalence.asd diff -u cl-prevalence/cl-prevalence.asd:1.1.1.1 cl-prevalence/cl-prevalence.asd:1.2 --- cl-prevalence/cl-prevalence.asd:1.1.1.1 Sun Jun 20 12:13:38 2004 +++ cl-prevalence/cl-prevalence.asd Mon Jun 28 04:57:26 2004 @@ -1,6 +1,6 @@ ;;;; -*- Mode: LISP -*- ;;;; -;;;; $Id: cl-prevalence.asd,v 1.1.1.1 2004/06/20 19:13:38 scaekenberghe Exp $ +;;;; $Id: cl-prevalence.asd,v 1.2 2004/06/28 11:57:26 scaekenberghe Exp $ ;;;; ;;;; The CL-PREVALENCE ASDF system definition ;;;; @@ -30,6 +30,8 @@ (:file "prevalence" :depends-on ("serialization")) (:file "debug-prevalence" :depends-on ("prevalence")) (:file "managed-prevalence" :depends-on ("prevalence")) + (:file "sysdeps" :depends-on ("package")) + (:file "master-slave" :depends-on ("prevalence" "sysdeps")) (:file "blob" :depends-on ("managed-prevalence"))))) :depends-on (:s-xml))

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[cl-prevalence-cvs] CVS update: cl-prevalence/src/prevalence.lisp
by Sven Van Caekenberghe 28 Jun '04

28 Jun '04

Update of /project/cl-prevalence/cvsroot/cl-prevalence/src In directory common-lisp.net:/tmp/cvs-serv17101/src Modified Files: prevalence.lisp Log Message: introduced transaction-hook turned *serialization-state* into an instance variable in prevalence-system bugfixes to filenaming methods Date: Mon Jun 28 04:56:35 2004 Author: scaekenberghe Index: cl-prevalence/src/prevalence.lisp diff -u cl-prevalence/src/prevalence.lisp:1.4 cl-prevalence/src/prevalence.lisp:1.5 --- cl-prevalence/src/prevalence.lisp:1.4 Sun Jun 27 09:37:10 2004 +++ cl-prevalence/src/prevalence.lisp Mon Jun 28 04:56:35 2004 @@ -1,6 +1,6 @@ ;;;; -*- mode: Lisp -*- ;;;; -;;;; $Id: prevalence.lisp,v 1.4 2004/06/27 16:37:10 scaekenberghe Exp $ +;;;; $Id: prevalence.lisp,v 1.5 2004/06/28 11:56:35 scaekenberghe Exp $ ;;;; ;;;; Object Prevalence in Common Lisp ;;;; @@ -96,7 +96,14 @@ (file-extension ;; type string :accessor get-file-extension :initarg :file-extension - :initform "xml")) + :initform "xml") + (serialization-state ;; type serialization-state + :reader get-serialization-state + :initform (make-serialization-state)) + (transaction-hook ;; type function + :accessor get-transaction-hook + :initarg :transaction-hook + :initform #'identity)) (:documentation "Base Prevalence system implementation object")) (defclass guarded-prevalence-system (prevalence-system) @@ -190,8 +197,6 @@ (defmethod remove-root-object ((system prevalence-system) name) (remhash name (get-root-objects system))) -(defparameter *serialization-state* (make-serialization-state)) - (defmethod execute ((system prevalence-system) (transaction transaction)) "Execute a transaction on a system and log it to the transaction log" (let ((result @@ -202,13 +207,21 @@ ";; Notice: system rollback/restore due to error (~a)~%" condition) (restore system))))) - (execute-on transaction system))) - (out (get-transaction-log-stream system))) - (funcall (get-serializer system) transaction out *serialization-state*) - (terpri out) - (finish-output out) + (execute-on transaction system)))) + (log-transaction system transaction) result)) +(defmethod log-transaction ((system prevalence-system) (transaction transaction)) + "Log transaction for system" + (let ((out (get-transaction-log-stream system))) + (funcall (get-serializer system) transaction out (get-serialization-state system)) + (terpri out) + (finish-output out))) + +(defmethod log-transaction :after ((system prevalence-system) (transaction transaction)) + "Execute the transaction-hook" + (funcall (get-transaction-hook system) transaction)) + (defmethod query ((system prevalence-system) function &rest args) "Execute an exclusive query function on a sytem" (apply function (cons system args))) @@ -230,7 +243,7 @@ snapshot))) (with-open-file (out snapshot :direction :output :if-does-not-exist :create :if-exists :supersede) - (funcall (get-serializer system) (get-root-objects system) out *serialization-state*)) + (funcall (get-serializer system) (get-root-objects system) out (get-serialization-state system))) (when (probe-file transaction-log) (copy-file transaction-log (merge-pathnames (make-pathname :name (get-transaction-log-filename timetag) :type (get-file-extension system)) @@ -261,7 +274,7 @@ (close-open-streams system) (when (probe-file (get-snapshot system)) (with-open-file (in (get-snapshot system) :direction :input) - (setf (get-root-objects system) (funcall (get-deserializer system) in *serialization-state*)))) + (setf (get-root-objects system) (funcall (get-deserializer system) in (get-serialization-state system))))) (when (probe-file (get-transaction-log system)) (let ((position 0)) (handler-bind ((s-xml:xml-parser-error @@ -273,7 +286,7 @@ (return-from restore)))) (with-open-file (in (get-transaction-log system) :direction :input) (loop - (let ((transaction (funcall (get-deserializer system) in *serialization-state*))) + (let ((transaction (funcall (get-deserializer system) in (get-serialization-state system)))) (setf position (file-position in)) (if transaction (execute-on transaction system) @@ -316,11 +329,11 @@ (defmethod get-transaction-log-filename ((system prevalence-system) &optional suffix) "Return the name of the transaction-log filename, optionally using a suffix" - (format nil "transaction-log@[-~a]" suffix)) + (format nil "transaction-log~@[-~a~]" suffix)) (defmethod get-snapshot-filename ((system prevalence-system) &optional suffix) "Return the name of the snapshot filename, optionally using a suffix" - (format nil "snapshot@[-~a]" suffix)) + (format nil "snapshot~@[-~a~]" suffix)) ;;; Some file manipulation utilities

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