From: Mark Volkmann <r.mark.volkmann@...>
Date: 2006-03-24T02:52:15+09:00
Subject: Re: Problem seeing classes in rubygem

On 3/23/06, Ross Bamford <rossrt@roscopeco.co.uk> wrote:
> On Fri, 2006-03-24 at 01:51 +0900, Wes Gamble wrote:
> > I have installed the gem correctly (it shows up when I do gem -list) and
> > my require_gem statement succeeds.
> >
> > However, when I go to instantiate one of the classes defined in this
> > gem, the call fails with:
> >
> > unitialized constant: BeautifulSoup
> >
> > on line 4 of my test case below.
> >
> > Here is my test case:
> >
> > require 'rubygems'
> > require_gem 'rubyful_soup', '>= 1.0.4'
> >
> > parser = BeautifulSoup.new(%{"kajsdlfkjads"})
>
> require_gem does (by default) actually require anything inside the gem -

I assume you meant "doesn't" above. A caveat is what you mention below
regarding autorequire.

> it's just used to tell Gems about version constraints you want to have.
> You'll still have to require 'rubyful_soup' to actually load it.
>
> note 1: In normal use, Gems patches require to automatically load gems
> as needed, so you could have just had "require 'rubyful_soup'" and the
> latest installed version would be installed. If you really do need that
> version constraint, however, I think you have to keep the require_gem.
>
> note 2: Gems does support an 'autorequire' attribute in a gem's spec
> that allows it to automatically require a given file when the Gem itself
> is required, but this is deprecated and rubyful soup doesn't appear to
> use it.

Based on what you've said it seems that
1) There is no point in using require_gem unless you want to specify
version constraints instead of just using the newest version of the
gem.
2) Since autorequire is being deprecated, you should never just use
require_gem. You should also use a require to pull in a specific file
within the gem.

Does anyone disagree with these recommendations?

--
R. Mark Volkmann
Object Computing, Inc.