Rails のインストールで file ‘lib’ not found と怒られたら 答: –no-ri –no-rdoc すればいい。 % gem install rails Fetching: rails-3.1.0.gem (100%) Successfully installed rails-3.1.0 1 gem installed Installing RDoc documentation for rails-3.1.0... file 'lib' not found % gem install rails --no-ri --no-rdoc Fetching: rails-3.1.0.gem (100%) Successfully installed rails-3.1.0 1 gem installed おしまい