#!/usr/local/bin/xotclsh
# $Id: s.persistenceExample.xotcl 1.4 01/03/23 21:55:32+01:00 neumann@somewhere.wu-wien.ac.at $
#
# load the persistence component
package require xotcl::store::persistence

# Two example objects
Object o
# set two variables to default values
o set x 1
o set y 1

Object p
# set two variables to default values
p set x 1
p set y 1

####################################
# now we make these vars persistent
####################################


# 1. we need the PersistenceMgr (for gdbm we have to specify a file
# name). If we want to get rid of the current setting and start again
# we default values, we have to delete this file
PersistenceMgr pmgr -dirName . -fileName example-db

# 2. we have to make the objects persistent. We register the
# persistence strategy as per-object mixin on the two objects
#
# one uses the lazy, one the eager strategy

o mixin Persistent=Eager
p mixin Persistent=Lazy

# 3. tell the objects, which PersistenceMgr to use

o persistenceMgr pmgr
p persistenceMgr pmgr

# 4. make the vars persistent

o persistent {x y}
p persistent {x y}

#####################################

# now the vars are loaded from the persistence store
#
# we incr them to demonstrate the persistency; and print the results

o incr x 2
o append y 1
p incr x 3
p append y 2

puts "Values:"
puts "  o->x: [o set x]"
puts "  o->y: [o set y]"
puts "  p->x: [p set x]"
puts "  p->y: [p set y]"

# now run the program several times to see the results 