From: Stefano Crocco <stefano.crocco@...>
Date: 2008-06-10T16:55:44+09:00
Subject: Re: yaml issues

On Tuesday 10 June 2008, jonty wrote:
> If you require a file in IRB it will output 'true' if it is there
>
> Therefore there is a problem with your installation

Not exactly. The line

require 'something'

returns true only if the file something.rb (or something.so or something.dll 
if it is a C extension) has been loaded. If that file has already been loaded, 
it won't be loaded again and require will return false. For example:

irb(main):001:0> require 'yaml'
=> true
irb(main):002:0> require 'yaml'
=> false

The first time, yaml.rb is indeed loaded, and require returns true. The second 
time, instead, require notices yaml.rb is already there (in particular, it 
looks in the $" global variable), doesn't reload it and returns false.

Stefano