This question already has an answer here:

Given a string, take all of its substrings (including the empty string). For example, given $abc$, we can form a set $\{\emptyset, a, b, c, ab, bc, abc\}$.

Given a regular language, take all the substrings of each of its strings, and form a language thereof. I wonder if the formed language is still regular?

Btw, is there a name for such an operation? In some sense, it is similar to taking the powerset of a set.



merged by Gilles Jun 9 '14 at 23:55

This question was merged with Regularity of “middles” of words from regular language because it is an exact duplicate of that question.

Browse other questions tagged or ask your own question.