try {
if (args.length==0)
System.err.println("Give a file name to convert");
else {
System.out.println("Starting conversion of file " + args[0]);
Convert2opSem c = new Convert2opSem(args[0]);
c.convert();
}
} catch (ExceptionJava2opSem e) {
System.err.println(e.getMessage());
}