A set of example programs for handling external core format.

In particular, typechecker and interpreter give a precise semantics.

To build, run "make".

To run the checker and interpreter (which currently aren't working anyway),
you need to generate External Core for all the base, integer and ghc-prim
libraries. This can be done by adding "-fext-core" to the GhcLibHcOpts in
your build.mk file, then running "make" under libraries/.
Then you need to edit Driver.hs and change "baseDir" to point to your GHC
libraries directory.

Most recently tested with GHC 6.8.2. I make no claims of portability. --tjc