From: ts <decoux@...>
Date: 2002-01-24T19:22:02+09:00
Subject: Re: Problem with Marshal in bdb-0.2.9

>>>>> "A" == Albert Wagner <alwagner@tcac.net> writes:

A>     /* don't use please */

 Yes, there are many comments in bdb :-)

A> So then, am I to understand that "_dump" and "_load" do not work in the bdb 
A> implementation of Marshal?  

 When you write

  a = BDB::Btree.new(..., "marshal" => true)

 the result is a delegator, this is the delegator which read and write the
 object from the db file by calling the singleton methods ::load and ::dump

 This mean that when you write

   module BDB
      class A < Btree
         extend Marshal
      end
   end

 you have just given two singleton methods (::load and ::dump) to BDB::A and
 you can write it

   module BDB
      class A < Btree
         class << self
            def load(a)
               Marshal.load(a)
            end
            def dump(a)
               Marshal.dump(a)
            end
         end
      end
   end

 it will do exactly the same thing.

 When you call #to_orig you retrieve the original object without its
 delegator, this mean that if you modify the object the modification will
 not be in the db file.


Guy Decoux