@hackage ottparse-pretty0.1.2.6

Ott (http://www.cl.cam.ac.uk/~pes20/ott/) is a tool for writing formal definitions of programming languages and calculi. Often the Ott grammars one defines end up being ambiguous, and Ott signals its displeasure by spewing forth several massive parse trees in a format requiring formidable patience to read. Finding the slight differences between two such parse trees is an exercise in seizure-inducing tedium.

To the rescue comes ottparse-pretty! Simply paste in each parse and it is shown to you in a nicely formatted tree form with all the extra meaningless cruft removed.