No thanks.

In extreme cases, such as j.jiggle () taking 10 minutes, then you might want to check before it. I gave a sketch of a programming pattern - it wasn't intended to be an exact solution for every possible programming problem. If you use it, you will still need to apply some intelligence of your own.

Note further, I was not even claiming that this is *THE* pattern to solve all error-handling. I was just giving it as an example, for consideration, as you earlier had asked for examples of error handling without exceptions (well, you asked for a goto error-exit pattern example, but I assumed other examples would also be allowed).

Object mutability: If an object is immutable, then its state doesn't change and will be immutable. Clearly there is little point in applying state-tracking patterns to single-state objects. This pattern applies to objects with a finite multiplicity of states. Despite your contention, I am fairly sure programming is full of such objects.

Even if you use a series of immutable objects and transition between them, you will still have an FSM with mutable state at a level above those immutable objects, implicitly or explicitly.