From: ts <decoux@...>
Date: 2003-07-09T23:09:32+09:00
Subject: Re: Marshaling objects partially

>>>>> "T" == Tanaka Akira <akr@m17n.org> writes:

T> When object A and B refer each other, which _load is called first?

 I must say that I've not understood

svg% cat b.rb
#!/usr/bin/ruby
class C
   attr_accessor :ref
   @@dumped = {}
   @@loaded = []
   @@num = 0

   def _dump(limit)
      if @@dumped[self]
         "\000#{@@dumped[self]}\000"
      else
         @@dumped[self] = @@num
         @@num += 1
         Marshal.dump([@ref], limit-1)
      end
   end

   def self._load(str)
      if /\A\000(\d+)\000\z/ =~ str 
         obj = @@loaded[$1.to_i]
      else
         obj = self.new
         @@loaded.push(obj)
         obj.ref = Marshal.load(str).shift
      end
      obj
   end
end

a = C.new
b = C.new  

a.instance_eval { @ref = b; @xxx = STDIN }
b.instance_eval { @ref = a; @xxx = STDIN }

p a
m = Marshal.dump(a)
c = Marshal.load(m)
p c
p c.ref

svg% 

svg% b.rb
#<C:0x40098e30 @ref=#<C:0x40098d40 @ref=#<C:0x40098e30 ...>, @xxx=#<IO:0x4009f348>>, @xxx=#<IO:0x4009f348>>
#<C:0x40098b60 @ref=#<C:0x40098ad4 @ref=#<C:0x40098b60 ...>>>
#<C:0x40098ad4 @ref=#<C:0x40098b60 @ref=#<C:0x40098ad4 ...>>>
svg% 


Guy Decoux