From: Richard Kilmer <rich@...>
Date: 2003-03-19T14:19:09+09:00
Subject: Re: XML too hard (YAML opportunity?)

I got this weird sense that people were talking about me...and here you 
are!

First, YAML and XML are different.

XML is a format for writing data, YAML is format for serializing 
language objects.  That is different.  If I wanted to take a series of 
Ruby objects and write out an XML file that contained their attributes 
I would write emitter code (possibly as methods on the object 
'to_xml'...possibly as a separate method/class), and parser code to 
read them in and construct instances.  If my Ruby model changed, I 
would keep the emitters/parsers updated.  A bit of a pain to be sure.

With YAML, I write Ruby code (but no emitters and parsers).  I craft my 
objects a bit with YAML (with to_yaml_properites, etc) but that is 
really for attribute order/readability...but nothing like XML.  And 
YAML is compact, yet readable (and simply editable).  The configuration 
files of FreeRIDE used to contain only string values because it was 
XML...we could have supported a "type" attribute, but you would still 
have been limited.  Now you can store anything in a configuration file, 
which is liberating.  That something is a boolean, string, integer, 
array, hash or whatever...YAML deals with for me.  That is really nice. 
  Oh, and did I say that YAML files are readable?

Here is a simple FreeRIDE plugin configuration file:

--- !ruby/object:FreeBASE::PluginConfiguration
name: rubyide_util_logger
version: 1.0
autoload: true
require_path: freebase/logger
startup_module: FreeBASE::Plugins::Logger

That's it...YAML parses that and creates a PluginConfiguration object 
for me.  Simple.  Oh, and version is a float, autoload is a boolean, 
etc, etc.

BTW:  I use XML quite a bit too, I am just stating a bit of the case 
for YAML's value.

-rich

On Tuesday, March 18, 2003, at 11:35  PM, <jbritt@ruby-doc.org> wrote:

>
>>
>> The only example I can/will give is Rich Kilmer,
>> who is a YAML enthusiast (and who impresses me
>> with his technical ability). He, of course, is
>> the reason FreeRIDE uses YAML.
>
> Yes, I know, and YAML is perhaps better for config files where
> name=value is too weak and XML is overkill.
>
> (BTW, does YAML support external entities?)