Prototype implementation of type inference for higher-rank types
	~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This is a small but complete implementation of type inference for higher-rank
types.  There are the following files:

  Main.lhs	   Test harness

  TcTerm.lhs	   The main type inference engine

  TcMonad.lhs	   The type inference monad

  BasicTypes.lhs   Data type declarations, for terms and types

  Parser.lhs	   A simple combinator parser



To get started:

	ghci Main.lhs

The prompt type

	tcs "\\x.x"

to type-check an expression written as a literal string, or

	tcf "foo.test"

to type-check an expression in a file foo.test



Shortcomings:
  Error messages are very poor
  The language is too small to be much fun