target :CodegenExample do
  type :console
  src ['main.cpp', 'generator.rb']
  src %w(src1.h src2.h), :force, prefix: 'generated/'
  rule do
    input '*.xyz'
    output 'generated/$(input.basename_no_ext).cpp'
    implicit_input 'generator.rb'
    cmd 'ruby $(implicit_input) $(input) $(output)'
    msg '$(input.basename) -> $(output.basename)'
  end
end