Add another TODO.

diff --git a/doc/TODO b/doc/TODO
index 99d0da87cf7a8113c87bbd6d6e84d44ddde5a910..73b79b02d9c5a231bc27076acba29a9bb3f6458a 100644 (file)
--- a/doc/TODO
+++ b/doc/TODO
@@ -8,5 +8,6 @@
 * Use distribution combinators[1] to get rid of the orphan instance
   warnings.
 
+* Update show definitions.
 
 [1] http://stackoverflow.com/questions/4001861/how-small-should-i-make-make-modules-in-haskell