Experience with Higher Order Rewriting from the Compiler Teaching Trenches

ABSTRACT. We have now twice used the ``HACS'' compiler generator tool in an NYU graduate Compiler Construction class. HACS is based on a higher-order rewriting formalism, thus we have effectively been teaching students higher order rewriting techniques as the way to implement compilers. In this paper we report on how HACS matches specific rewriting notions to the techniques used by compiler writers, and where the main difficulties have been encountered in teaching these.