How to use
----------

ghci -F -pgmF ./adt_view YOUR_SOURCE
or 
ghc  -F -pgmF ./adt_view --make YOUR_SOURCE


e.g.:

ghci -F -pgmF ./adt_view -i./lib examples/queue.hs
ghci -F -pgmF ./adt_view -i./lib examples/sized_tree.hs