Show-ing GHC internal data structures

[David William Simmons-Duffin]

I'm working with a friend on a project that involves hacking at the GHC
internals.  We'd like to be able to print some of the large data
structures involved -- specifically a TcGblEnv.  TcGblEnv is a record with
a number of fields of different types, and it would be silly to go through
the source adding "deriving Show" to the end of each type definition.

It seems like Show instances for internal data structures would be useful
for the GHC developers (for debugging purposes -- perhaps they were left
out of the GHC distribution to keep the compiled code small?), and we were
wondering if anyone had the relevant instance declarations lying around.

Thanks,
David