In some ways, runtime is like the Wild West. Even if you release bug-free code, you have no way to guarantee that the code calling your code (or the data imported from a file or the value a user enters) is also error-free. For example, let’s say that your code performs a numerical division using parameters supplied by an end user at runtime. The user enters a divisor, zero, that is given as a parameter to your function. The result is a “division by zero” error. Or, you have a method that works only if it’s given an object, and at runtime it gets a LotusScript nothing (an empty object reference), which results in the infamous “Object variable not set” error so beloved by LotusScript developers. These error messages tell you little more than that an error occurred. They can’t help you trace the cause of the problem.

Of course, you can (and sometimes have to) use the debugger to step through your code. But you also have to be able to reproduce the error, which can be especially difficult if it occurs, for example, at a customer site that you can not access directly. At Foconis, we’ve discovered that simply having a detailed error message completely eliminates the need for time-consuming debugging sessions (or plain guesswork) in the majority of cases.

Using the Foconis Object Framework (FOF), which is a production-ready, free, open-source LotusScript library, you can get more helpful information when a runtime error occurs — information that will tell you exactly where the error occurred and why — and you can do it without writing a lot of code. We’ll show you how.