let options = ref [
"-gen", Arg.Set generate_code, Rep_messages.opt_gen ;
"-ibin", Arg.Set binary_input, Rep_messages.opt_bin_in ;
"-obin", Arg.Set binary_output, Rep_messages.opt_bin_out ;
"-o", Arg.String (fun s -> output_file := Some s), Rep_messages.opt_out ;
]