即使安装了 gem，Ruby 也找不到所需的库

Question

我花了几天时间尝试安装 ruby​​ 1.9.2 并让它与 gems 一起工作:-/我最终放弃了我的 Mac OSX 10.6 机器，下面是我的 Ubuntu 机器上的当前状态。任何建议将不胜感激!

# ruby test.rb
<internal:lib/rubygems/custom_require>:29:in `require': no such file to load -- mongo (LoadError)
 from <internal:lib/rubygems/custom_require>:29:in `require'
 from test.rb:1:in `<main>'
# cat test.rb
require 'mongo'
db = Mongo::Connection.new.db("mydb")
# gem which mongo
/usr/local/rvm/gems/ruby-1.9.2-p0/gems/mongo-1.1.2/lib/mongo.rb
# cat /etc/lsb-release 
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=10.10
DISTRIB_CODENAME=maverick
DISTRIB_DESCRIPTION="Ubuntu 10.10"

根据此页面:http://docs.rubygems.org/read/chapter/19我符号链接(symbolic link)了我正在使用的 ruby 以匹配正在使用的 gem :

# which ruby
/usr/local/rvm/bin/ruby
# ls -l `which ruby`
lrwxrwxrwx 1 root root 44 2010-11-17 13:25 /usr/local/rvm/bin/ruby -> /usr/local/rvm/rubies/ruby-1.9.2-p0/bin/ruby
# gem env | grep 'RUBY EXECUTABLE'
  - RUBY EXECUTABLE: /usr/local/rvm/rubies/ruby-1.9.2-p0/bin/ruby
# which gem
/usr/local/rvm/bin/gem
# gem -v
1.3.7
# ruby -v
ruby 1.9.2p0 (2010-08-18 revision 29036) [i686-linux]

Answer 1

尝试将以下行放在开头

require "rubygems"