# YAML in limbo?

**URL:** <https://www.ruby-forum.com/t/yaml-in-limbo/94345>\
**Category:** Ruby\
**Created:** [May 1, 2006, 2:05pm UTC](https://www.ruby-forum.com/t/yaml-in-limbo/94345 "2006-05-01T14:05:39Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![ohad](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/o/f04885/32.png) [@ohad](https://www.ruby-forum.com/u/ohad)\
**Post date:** [May 1, 2006, 2:05pm UTC](https://www.ruby-forum.com/t/yaml-in-limbo/94345/1 "2006-05-01T14:05:39Z")

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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?

---

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**Author:** ![ohad](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/o/f04885/32.png) [@ohad](https://www.ruby-forum.com/u/ohad)\
**Post date:** [May 3, 2006, 6:57pm UTC](https://www.ruby-forum.com/t/yaml-in-limbo/94345/2 "2006-05-03T18:57:50Z")

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Ohad L. wrote:

> ```
> }
> 
> ```
> 
> to be unused.

Here’s how you do it these days:

class IPAddr  
yaml\_as “tag:ruby.yaml.org,2002:ipaddr”  
def to\_yaml(opts = {})  
YAML::quick\_emit(object\_id, opts) do |out|  
out.scalar(taguri, self.value, :plain)  
end  
end  
end

I started doing RDoc for everything. I keep forgetting to wrap it up.

\_why

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<div class="post-metadata">

**Author:** ![ohad](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/o/f04885/32.png) [@ohad](https://www.ruby-forum.com/u/ohad)\
**Post date:** [May 4, 2006, 10:28am UTC](https://www.ruby-forum.com/t/yaml-in-limbo/94345/3 "2006-05-04T10:28:57Z")

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why the lucky stiff wrote:

> Here’s how you do it these days:
> 
> …
> 
> I started doing RDoc for everything. I keep forgetting to wrap it up.
> 
> \_why

Much thanks. That IS simpler… how do I handle the importing though?

(BTW you rule dude 🙂 )