From: Joshua Choi <rbysamppi@...>
Date: 2007-01-14T11:29:20+09:00
Subject: yaml.rb and YAML "%" directives

I'm new to Ruby, and it really is fun. Right now, I'm playing with YAML...

...but one part of yaml.rb doesn't seem to work--it doesn't seem to
recognize any % directives
(http://yaml.org/spec/current.html#id2523453) like "%YAML 1.1" or
"%TAG ! tag:blah.com,2007:".

Why might it not be working?

I'm using Ubuntu Dapper, Ruby v1.8.4. The versions of yaml and syck
I'm using are the ones that came with Ruby/Ubuntu.

Thanks in advance,
Joshua Choi

(My test case is from the YAML 1.1 spec:

%TAG ! tag:clarkevans.com,2002:
--- !shape
  # Use the ! handle for presenting
  # tag:clarkevans.com,2002:circle
- !circle
  center: &ORIGIN {x: 73, y: 129}
  radius: 7
- !line
  start: *ORIGIN
  finish: { x: 89, y: 102 }
- !label
  start: *ORIGIN
  color: 0xFFEEBB
  text: Pretty vector drawing.

And if I do this:
require 'yaml'
dump = YAML.load(...what's above...)
puts dump.to_yaml

...it prints:
---
"%TAG ! tag:clarkevans.com,2002":

Apparently, it's interpreting the top line as a string instead of a
directive; the rest of the document was cut off by the top "---".

It works if the top line isn't there or is below the "---", and it
doesn't work if there's any line starting with "%" above "---" ; if
it's below "---", it gets interpreted as a string.)