def build_modern_index(index, file, name)
    say "Generating #{name} index"

    Gem.time "Generated #{name} index" do
      open(file, 'wb') do |io|
        specs = index.map do |*spec|
          # We have to splat here because latest_specs is an array, while the
          # others are hashes.
          spec = spec.flatten.last
          platform = spec.original_platform

          # win32-api-1.0.4-x86-mswin32-60
          unless String === platform then
            alert_warning "Skipping invalid platform in gem: #{spec.full_name}"
            next
          end

          platform = Gem::Platform::RUBY if platform.nil? or platform.empty?
          [spec.name, spec.version, platform]
        end

        specs = compact_specs(specs)
        Marshal.dump(specs, io)
      end
    end
  end
#
Build a single index for RubyGems 1.2 and newer