Ruby + Shotgun：编辑我刚刚收到的文件时出现错误信息

Question

完成新手，刚收到一个Web应用程序。 Shotgun可以与原始文件一起使用，但在编辑后不能。收到以下消息：

  

/usr/local/rvm/rubies/ruby-1.9.3-p448/lib/ruby/1.9.1/rubygems/dependency.rb:247:in   来自to_specs': Could not find shotgun (>= 0) amongst [rvm-1.11.3.8] (Gem::LoadError) from /usr/local/rvm/rubies/ruby-1.9.3-p448/lib/ruby/1.9.1/rubygems/dependency.rb:256:in to_spec'   /usr/local/rvm/rubies/ruby-1.9.3-p448/lib/ruby/1.9.1/rubygems.rb:1231:in   gem' from /usr/local/rvm/rubies/ruby-1.9.3-p448/bin/shotgun:22:in “

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