https://swtch.com/~rsc/regexp/
https://wiki.haskell.org/Regex_Posix
Sulzmann
--------
http://www.home.hs-karlsruhe.de/~suma0002/publications/posix-derivatives.pdf
Matt Might lexers
-----------------
http://matt.might.net/articles/lexers-in-racket/
http://matt.might.net/articles/parsing-bibtex/
http://matt.might.net/articles/nonblocking-lexing-toolkit-based-on-regex-deriva
Uncool compiler
---------------
https://github.com/jsnider3/Scales
http://jsnider3.github.io/update/scala/uncool/compiler/2015/06/11/uncool-in-scala/