class Gem::RequestSet

def install_from_gemdeps options, &block
  gemdeps = options[:gemdeps]
  @install_dir = options[:install_dir] || Gem.dir
  @prerelease  = options[:prerelease]
  @remote      = options[:domain] != :local
  @conservative = true if options[:conservative]
  gem_deps_api = load_gemdeps gemdeps, options[:without_groups], true
  resolve
  if options[:explain]
    puts "Gems to install:"
    sorted_requests.each do |spec|
      puts "  #{spec.full_name}"
    end
    if Gem.configuration.really_verbose
      @resolver.stats.display
    end
  else
    installed = install options, &block
    if options.fetch :lock, true then
      lockfile =
        Gem::RequestSet::Lockfile.build self, gemdeps, gem_deps_api.dependencies
      lockfile.write
    end
    installed
  end
end