From: matz@... (Yukihiro Matsumoto)
Date: 2003-01-02T13:23:29+09:00
Subject: Re: How to extend Hash

Hi,

In message "How to extend Hash"
    on 03/01/02, TOTO <zhoujing@comp.nus.edu.sg> writes:

|I am trying to extend the Hash class so that I can "Insert the content
|of a Hash object to another Hash object".
|
|However, the internal code for Hash is written in c. Is it possible to
|extend the class using ruby itself? How, since we don't know the
|internal data structures of class Hash.

It is possible, just like other Ruby-defined classes.  But first you
can check out "update" method for Hash class.

							matz.

------------------------------------------------------------ Hash#update
     hsh.update( anOtherHash ) -> hsh
------------------------------------------------------------------------
     Adds the contents of anOtherHash to hsh, overwriting entries with
     duplicate keys with those from anOtherHash.
        h1 = { "a" => 100, "b" => 200 }
        h2 = { "b" => 254, "c" => 300 }
        h1.update(h2)   #=> {"a"=>100, "b"=>254, "c"=>300}