Switching to def :case costed[1] me 28 LoC.
(e3cda3b487eb4280215bc322101e7844f7f7656c to 3d58df8ba744ff6e8c182b49206448addb9273ed)
[1] http://akkartik.name/blog/28672493
https://github.com/akkartik/wart/compare/e3cda3b487eb4280215...
Now I'm not so sure. :-p It would take some effort to comprehend all those changes at once.
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