Need a way troubleshoot a formula by stepping through it piece-by-piece

Much like most coding languages or even excel's formulas, to aid in writing complex code / formulas, there needs to be some way for a developer / builder to see how the individual components of it resolve one by one.  

I'd like a way to step through a formula to see where it's going wrong, and see values of the components so that I can more easily troubleshoot it.