I found the best way to debug a complex piece of scala code was to get rid of as much laziness and deferral as possible. Creating a huge lazy sequence that propagated through multiple call-layers was absolutely evil. Also, options, although strict, are troublesome across more than a couple of lines of code given the way they crash. In general, only use option if failure is expected, otherwise null is your friend!
For simple programs that do not need to be debugged, laziness is great, you can write some very concise code. Once you are debugging however, you want to expose as much control flow as possible to break and step through. I say this from writing 10s of thousands of Scala code in a fairly complicated context (Scala compiler + Eclipse) with non-trivial control flow (mostly event driven).
For simple programs that do not need to be debugged, laziness is great, you can write some very concise code. Once you are debugging however, you want to expose as much control flow as possible to break and step through. I say this from writing 10s of thousands of Scala code in a fairly complicated context (Scala compiler + Eclipse) with non-trivial control flow (mostly event driven).