public void Test_formal_usage()
{
const string DOC =
"Usage: prog [-hv] ARG\r\n" +
" prog N M\r\n" +
"\r\n" +
" prog is a program.";
var usage = Docopt.ParseSection("usage:", DOC).First();
Assert.AreEqual("Usage: prog [-hv] ARG\r\n prog N M", usage);
Assert.AreEqual("( [-hv] ARG ) | ( N M )", Docopt.FormalUsage(usage));
}