mortee wrote:
> Replying to myself: it turned out that I was using the wrong way to
> check if I can require the given gem, and actually rubygems works just
> fine. This transformed my problem into another question. What's the
> difference between the following two cases?
> 
> $ ruby -rsome-gem -e 'puts "ok"'
> ruby: no such file to load -- some-gem (LoadError)
> $ ruby -e 'require "some-gem"; puts "ok"'
> ok
> $
> 
> mortee wrote:
>> Hi,
>>
>> I have a problem with rubygems on a OS X 10.4.10 Tiger PPC. Ruby 1.8.6
>> and rubygems 0.9.4 are installed properly. Ruby is installed through
>> fink so I set PREFIX to /sw. I installed rubygems by
>>
>> PREFIX=/sw
>> export GEM_HOME=$PREFIX/lib/ruby/gems/1.8
>> export RUBYLIB=$PREFIX/lib/ruby:$PREFIX/lib/site_ruby/1.8
>> sudo ruby setup.rb all --prefix=$PREFIX
>>
>> so it should be aware of the repository path. I installed some gems, the
>> gem list command shows them as expected.
>>
>> I have -rubygems in RUBYOPT.
>>
>> But when I simply require any gem by name, I get a LoadError (on the
>> file, not rubygems itself). If I specify the absolute path of the gem's
>> main file to require, it passes without error.
>>
>> What may be wrong with my setup?
>>
>> thx
>> mortee
>>
>>
>>
> 
> 

Before you can require a gem, you must require RubyGems. This occurs 
automatically for you because you have -rubygems in RUBYOPT. However, 
when you using the -r option to require a file, Ruby doesn't 
automatically require RubyGems, so Ruby can't find the thing you want to 
  require. The only kind of libraries you can require with the -r option 
are libraries that aren't gems.

I'm pretty sure this limitation will be removed in the next release of Ruby.

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