I have a blackbox program that generates a set of strings. What is the best regular expression learner that I can use to learn (approximate) what the blackbox program uses as a generator? Note that I only have positive examples. (Checking whether a string is accepted or rejected is possible but rather costly). I see that algorithms like RPNI and L* requires both positive and negative examples.
I especially want to avoid over-generalization.
Update: I have been making do with using Sequitur to identify repeating patterns in single strings, and then lining up the resulting patterns to identify common repetitions. However, this feels really kludgy and I would like to improve it. Is this the best one can do? are there better ways?