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+Regular Expression Hacks
+========================
+These scripts explore regular expressions in the formal sense---those that
+represent precisely the types of languages that can be decided by a finite
+state machine (Type-3 grammars in the Chomsky hierarchy).  This differs from
+the types of regular expressions typically found in text editors and
+programming languages, which are far more expressive.[0]
+
+I expect eventually to go into what makes this so interesting, but for the
+time being, know that these examples _can_ be solved more simply using
+features of modern regex engines.  Sed, for example, does support
+backreferences, which would have made certain examples here trivial to
+implement.  But then they wouldn't have very much hack value, would they?
+
+As such, these scripts are intentionally esoteric.  They are not things you
+should probably use in a production system.
+
+To run the, use the `animate' script.  If the sed script being run does not
+produce fixed-width frames, use the `-c' option.  Example inputs and
+commands can be found in many of the scripts.
+
+
+[0]: https://en.wikipedia.org/wiki/Regular_expression
+
+
+Copyright (C) 2018 Mike Gerwitz
+
+This file is released under the Creative Commons Attribution-ShareAlike 4.0
+International License.  See COPYING.CCBYSA for more information.