From: Ross Bamford <rosco@...>
Date: 2006-11-25T04:49:34+09:00
Subject: Re: Gem dependency (Hpricot)

On Wed, 22 Nov 2006 12:38:13 -0000, Han Holl <han.holl@gmail.com> wrote:

> Hi,
>
> This is from Hpricot's install page:
>
> If you'd prefer not to use RubyGems, you can also acquire a plain Ruby
> distribution: http://code.whytheluckystiff.net/dist/hpricot-0.4.tgz
>
> However, if you download, and try to build with rake, you get:
> bever:/usr/src/ruby/hpricot-0.4> rake
> (in /home/source/src/ruby/hpricot-0.4)
> rake aborted!
> no such file to load -- rubygems
> /home/source/src/ruby/hpricot-0.4/Rakefile:3:in `require'
> (See full trace by running task with --trace)
>
> So not preferring to use gems doesn't really buy you much.
>
> Han Holl
>
> PS I'm sending this to this list because Hpricot is not alone in this.
> Dependencies on gem are not good. Of course I'll give in, install gem,
> and subsequent dependencies will go unnoticed here, until I try to run
> something on a different computer.
>

I think that most projects whose Rakefile depends on Gems do so because  
they need Gem::Specification for the Rake GemPackageTask. Generally I tend  
to leave out an explicit require and do something like:

   require 'rubygems' rescue nil

   # .... later:

   if ! defined?(Gem)
     warn "Package Target requires RubyGEMs"
   else
     spec = Gem::Specification.new do |s|
       ...
     end
   end

-- 
Ross Bamford - rosco@roscopeco.remove.co.uk