using uCalcSoftware;

var uc = new uCalc();

static void MyFunc(uCalc.Callback cb) {
   // This error occurs during evaluation, not parsing.
   cb.Error.Raise("Manual evaluation failure!");
}

static void MyHandler(Handle_uCalc h) {
   var uc = new uCalc(h);
   Console.WriteLine($"Handler triggered for error: {uc.Error.Message}");
   Console.WriteLine($"ErrorExpression() returned: '{uc.Error.Expression}'");
   Console.WriteLine($"Is expression empty? {uc.Error.Expression == ""}");
}


uc.DefineFunction("MyFunc()", MyFunc);
uc.Error.AddHandler(MyHandler);

// The expression 'MyFunc()' itself is valid syntactically.
Console.WriteLine(uc.EvalStr("MyFunc()"));