Ahoy, hoy monks. I've got a problem to solve which seems like a perfect fit for a finite state machine. I've got an object which can be in exactly one state at a time. The set of possible states is complex - each one has a number of possible next states and rules for when those states are valid. When the object goes from one state to the next there may be actions to perform. To make matters worse, the set of possible states is very likely to change in the future as more is learned about the problem.

I figured I could get some help from CPAN, but so far my search has come up empty. DFA::Simple and DFA::Command both seem to be built specifically for parsing text coming from a filehandle. The events that would cause changes in my machine come from actions in a web application. I could bend over backwards to make them work for my problem but it'd be a tremendous hack. I could build something from scratch but it's hard to believe I'm the first to have this problem.

So I put these questions to you, kind monks:

  1. Am I right thinking that my problem calls for a FSA?
  2. Is there a module on CPAN which can help me?

-sam

In reply to Are state machines just for parsing? by samtregar

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