An import filter that take @imports in files inline

import_filter.rb

class ImportFilter < Rake::Pipeline::Filter
  def generate_output(inputs, output)
    inputs.each do |input|
      path = input.root + "/" + input.path.sub(/[^\/]+\.\w+/, "")
      print "#{path}\n"
      output.write input.read.gsub(/(@import\s+\"([^\"]+)\";)/) {
        File.read("#{path}#{$2}")
      }
    end
  end
end