[Haskell] Getting a function dependency graph from source

[Durward McDonell]

Hello.  This seems like a basic question, but I haven't
been able to find an answer.  I have a pile of Haskell
code that is compiled into a library, and a Haskell program
that uses this library.  What I would like is something
that will look at my program and follow the function calls
until it gets to the Prelude.  I want to know which functions
in the library and in the Prelude actually get used (at
least potentially).

I believe Hat only looks at traces of an actual run of the
program, and so doesn't quite give me what I want.  I also
think I could do this with the haskell-src library, but it
looks like a lot of work to understand that and use it.

Thanks.

-- 
Durward McDonell
durward.mcdonell at jhuapl.edu