# File lib/multiruby.rb, line 149
  def self.fetch_tar v
    require 'open-uri'
    base_url = "http://ftp.ruby-lang.org/pub/ruby"

    in_versions_dir do
      warn "    Determining latest version for #{v}"
      ver = v[/\d+\.\d+/]
      base = extract_latest_version("#{base_url}/#{ver}/", v)
      abort "Could not determine release for #{v}" unless base
      url = File.join base_url, ver, base
      warn "    Fetching #{base} via HTTP... this might take a while."
      open(url) do |f|
        File.open base, 'w' do |out|
          out.write f.read
        end
      end
    end
  end