But coming from the opposite direction, given a regular expression R, is it possible to generate the set of all strings that match R?

No, for the reason cited above in this thread. The best you can do is generate representative strings. Methings japhy did something along these lines a while back, but da*ned if I can find it.

In reply to Re: generating strings from a regular expression by dws
in thread generating strings from a regular expression by indapa

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