```ruby
module MetaCon
  module Loaders
    class RVM
      include MetaCon::Loaders::Helpers
      include MetaCon::CLIHelpers
      def self.ensure(dep, state, proj, v=true)
        kind = dep.shift
        if kind == 'ruby'
          vstr = dep[0].downcase=='head' ? 'ruby-head' : dep.join('-')
          switch_ruby(vstr)
        elsif kind == 'gem'

        else
          raise "I don't handle #{kind} dependencies... am I missing something?"
        end
      end

      def self.switch_ruby(version, v=true)
        # TODO: Be sure and always select a gemset
        # TODO: Make sure metacon is always installed in that gemset
        select_res, err_txt, st = cmd "rvm use '#{version}'", v
        select_res += err_txt
        if st == 0 && select_res =~ /rvm install (.*)/
          real_version = $1
          if install_ruby(real_version,v) then return switch_ruby(real_version)
          else return(false) end
        elsif select_res =~ /Using/i then return true
        else return(false) end
      end

      def self.install_ruby(version, v=true)
        inst_res, err_txt, st = cmd "rvm install '#{version}'", v
        return st == 0 && err_text.strip.length == 0
      end
    end
  end
end
```

Make sure and require the needed helpers
user
```ruby
module MetaCon
  module Loaders
    class RVM
      require 'metacon/loaders/helpers'
      include MetaCon::Loaders::Helpers
      include MetaCon::CLIHelpers
      def self.ensure(dep, state, proj, v=true)
        kind = dep.shift
        if kind == 'ruby'
          vstr = dep[0].downcase=='head' ? 'ruby-head' : dep.join('-')
          switch_ruby(vstr)
        elsif kind == 'gem'

        else
          raise "I don't handle #{kind} dependencies... am I missing something?"
        end
      end

      def self.switch_ruby(version, v=true)
        # TODO: Be sure and always select a gemset
        # TODO: Make sure metacon is always installed in that gemset
        select_res, err_txt, st = cmd "rvm use '#{version}'", v
        select_res += err_txt
        if st == 0 && select_res =~ /rvm install (.*)/
          real_version = $1
          if install_ruby(real_version,v) then return switch_ruby(real_version)
          else return(false) end
        elsif select_res =~ /Using/i then return true
        else return(false) end
      end

      def self.install_ruby(version, v=true)
        inst_res, err_txt, st = cmd "rvm install '#{version}'", v
        return st == 0 && err_text.strip.length == 0
      end
    end
  end
end
```
assistant