bos/aeson — pull request #73 by jhance (2012-03-18 13:06:58+00:00)
Title: Fix #72.

Sometimes, it appears, Nullary constructors can be encoded as Null as
well as an empty array [not sure why one this!]. The Generic code, as of
49befcafc80a85b371a6e0e0d5ab4ad9b33d8778, fails when a Null is
passed for a nullary constructor. Add in a pattern match to fix this
issue.

See https://github.com/bos/aeson/issues/72