From: Gennady <gfb@...>
Date: 2003-12-19T06:47:43+09:00
Subject: Re: Configuration Files


why the lucky stiff wrote:
> On Thursday 18 December 2003 10:11 am, Ara.T.Howard wrote:
> 
>>i'm with you (and use it myself), but the above is problematic if you
>>actually want non-programmers to be able to _configure_ a system.  for
>>example, how long do you think it would take a non-programmer to debug
>>this?
>>
>>file config.rb:
>>========
>>require 'yaml'
>>config = <<-txt
>>plugin:
>>  player:
>>    class: CommandPlayer
>>    command: mpg123
>>txt
>>YAML::load(config)
>>
>>
>>~/eg/ruby > ruby config.rb
>>/data/ruby-1.8.0//lib/ruby/1.8/yaml.rb:39:in `load': parse error on line 3,
>>col 12: `    command: mpg123' (ArgumentError) from
>>/data/ruby-1.8.0//lib/ruby/1.8/yaml.rb:39:in `load'
>>        from config.rb:8
>>
>>-a
> 
> 
> The above throws an error for you?  Man, a lot has been fixed since 1.8.0.


I use YAML form the latest ruby-1.8.1preview3, and when I 
copy-and-pasted the code from Ara's post, I got the same error. The 
problem was that there was a TAB character after "player:" (was it 
deliberately implanted to prove the point ;-) ?), and it caused the 
problem. If you remove TAB or convert it to spaces, everything starts 
working fine.

_why, could you just ignore trailing spaces and tabs?

Gennady.

> 
> Anyhow, I'm with ya.  So, let's solve the problem.  Would it help if you could 
> hook the parse error handler to generate your own nice errors?  We can also 
> start to provide more specific parse error messages, though this can be 
> needly on some edges.
> 
>   ~/eg/ruby > ruby config.rb
>   Error in configuration file.  See line 4.
> 
>             2  player:
>             3    class: CommandPlayer
>   Here!! -> 4      command: mpg123
> 
>   Yeah, the indentation on that line needs to be trimmed
>   a bit.  Just line it up cozy with the line above it.
> 
> _why
> 
>