process_const (TypeChecker)

    # File lib/type_checker.rb, line 378
      def process_const(exp)
        c = exp.shift
        if c.to_s =~ /^[A-Z]/ then
          # TODO: validate that it really is a const?
          type = @genv.lookup(c) rescue @env.lookup(c)
          return t(:const, c, type)
        else
          raise "I don't know what to do with const #{c.inspect}. It doesn't look like a class."
        end
        raise "need to finish process_const in #{self.class}"
      end