> Not know what a "finite state machine" was, I decided to poke around the > Net before replying to you. I found this definition: > ... > at http://www.c3.lanl.gov/mega-math/gloss/pattern/dfa.html > > This seems rather ambiguous, though, as it basically means that a FSM is > anything that you can imagine that can parse language. Nothing about its > inherent limits, outside of which I presume one will find irregular > languages.
IMHO that's an awful explanation. >From what I remember, this is true. Somebody correct me if I'm wrong. Any "Finite State Machine" or true "regular expression" can be written using a set of symbols (e.g. chars a-z) and three operators: * Concatenation - pattern A concatenated with B matches a match for A followed by a match for B * Or - pattern A-or-B matches either a match for A or a match for B. * Closure - zero or more matches for a pattern So regular expressions in Perl are really far from being regular. for technical definition, you can check e.g. http://www.wkonline.com/d/Finite_State_Machine.html but that is most likely not understandable without prior knowlegde. -- Markus Laire 'malaire' <[EMAIL PROTECTED]>
