[ruby-talk:10378] Re: Problems creating persistent objects

>>>>> "D" == Danny Sofer <[e-mail]> writes:

D> 2) by the time the finalizer is called, all my instance variables seem to
D> have disappeared, so i can't automatically store my data. any other
D> suggestions?

 WARNING wait confirmation from matz

 It seems to work with this patch (this is another problem with 1.7 :-))

pigeon% diff -u gc.c.old gc.c
--- gc.c.old    Fri Dec 22 04:21:56 2000
+++ gc.c        Mon Feb  5 18:51:29 2001
@@ -1227,7 +1227,7 @@
        p = heaps[i]; pend = p + HEAP_SLOTS;
        while (p < pend) {
            if (FL_TEST(p, FL_FINALIZE)) {
-               p->as.free.flag = 0;
+               FL_UNSET(p, FL_FINALIZE);
                run_final((VALUE)p);
            }
            p++;
pigeon% 


pigeon% cat b.rb
module Storage
  def store
    print "should be storing #{@f}\n"
    File.open(@f, "w") { |f| Marshal.dump(@data, f)  }
  end
  def retrieve
    File.open(@f) { |f| return Marshal.load(f) }
  end
end

class Obj
  include Storage
  def initialize(f, m='')
    @f = f
    puts "the file is #{@f}"
    @data = {}
    @data['m'] = ''
    if File.exists?(@f)
      @data = retrieve
    end
    puts "Old value : #{@data['m']}"
    @data['m'] = m
    puts "New value : #{@data['m']}"
    ObjectSpace.define_finalizer(self, proc { store } )
   end
end

o = Obj.new('.test', 'hello')
pigeon% 

pigeon% ruby b.rb
the file is .test
Old value : 
New value : hello
should be storing .test
pigeon% 

pigeon% ruby b.rb
the file is .test
Old value : hello
New value : hello
should be storing .test
pigeon% 


Guy Decoux