# File lib/rvm/environment/rubies.rb, line 25
    def use(ruby_string, opts = {})
      ruby_string = ruby_string.to_s
      result = rvm(:use, ruby_string)
      successful = result.successful?
      if successful
        @environment_name = ruby_string
        @expanded_name    = nil
        use_env_from_result! result if opts[:replace_env]
      end
      successful
    end