$ ll
total 48
-rw-r--r--  1 wallingf  staff  4161 Apr 16 10:21 interpreter.rkt
-rw-r--r--  1 wallingf  staff  4586 Apr 16 10:21 syntax-procs.rkt
-rw-r--r--  1 wallingf  staff  3631 Apr 16 10:21 tests.rkt
-rw-r--r--  1 wallingf  staff   792 Apr 16 10:21 utilities.rkt