Full disclosure, I'm interested in what this means about transformations on NFAs, but regex expressions seem like a easy way to ask the question.
If you have a regex that uses the plus operator (match one or more) can it, in the general case, be transformed into a regex that uses only the star operator (match zero or more).
Since all regular expressions can be converted into an NFA, and all NFAs can be converted into a regular expression (assuming the alphabet is the unicode character set lol), if it's true for one, it's true for both.
An hand-contrived example regex:
A regex recognizing the same language, without the + operator:
This may seem intuitively true for such a simple example, but I'd like to know for certain that it is generally true. Also, is there an algorithm that can convert an NFA containing a plus-like flow into a star-like flow NFA? Thanks!