#!/usr/bin/ruby require 'erb' mp3s = Dir['resources/*.mp3'].map { |path| File.basename(path, '.mp3') } template = ERB.new <<-EOF package { public class SoundModel { <% mp3s.each_with_index do |mp3, i| %> public static const SOUND_<%= mp3 %>:int = <%= i %>;<% end %> } } EOF puts template.result(binding)