From: Ohad Lutzky <lutzky@...>
Date: 2006-05-01T21:05:55+09:00
Subject: YAML in limbo?

When I was writing a simple DNS Sniffer/IDS (for a university project), 
I wanted to be able to export DNS responses to YAML, for later 
comparison (to detect spoofing). The IPAddr class was widely used within 
the project - however, its YAML export looks like this:

  irb(main):002:0> i = IPAddr.new('127.0.0.1')
  => #<IPAddr: IPv4:127.0.0.1/255.255.255.255>
  irb(main):003:0> y i
  --- !ruby/object:IPAddr
  addr: 2130706433
  family: 2
  mask_addr: 340282366920938463463374607431768211455

After much effort, I figured out how to get it to export like this:

  --- !ruby/ipaddr 64.233.167.99

This was done with the following code:

  class IPAddr
    def to_yaml_type
      "!ruby/ipaddr"
    end
    def to_yaml( opts = {} )
      YAML::quick_emit(self.object_id, opts) { |out|
        out << "#{to_yaml_type} "
        self.to_s.to_yaml(:Emitter => out)
      }
    end
  end

  YAML.add_ruby_type(/^ipaddr/) { |type, val|
    IPAddr.new(val)
  }

This works just fine in Ruby 1.8.3 (Syck 0.45), but b0rks completely in 
1.8.4 (Syck 0.6). The +out+ stream no longer has a << operator, and 
there is a pretty obvious error in the add_ruby_type method, which seems 
to be unused.

Now, _why says that the new version is much smarter about these kinds of 
things, but the documentation is currently [even more] lacking [than the 
previous versions']. So my question splits into two parts:

- How can I make my code work in the new version? (preferably 
backwards-compatibly)
- What's up with the docs?

-- 
Posted via http://www.ruby-forum.com/.