Execute HQ9+/Common Lisp is part of RCHQ9+. You may find other members of RCHQ9+ at Category:RCHQ9+.
The interpreter (in Common Lisp) accepts a string, treated as program text, or a pathname object, in which case the contents of the file are the program text.
(defun slurp (filespec) "Return the contents of the file as a string." (with-output-to-string (out) (with-open-file (in filespec :direction :input) (loop for line = (read-line in nil nil) until (null line) do (write-line line out))))) (defun hq9+ (input &optional (out *standard-output*)) "Execute the hq9+ program designated by input. If input is a string, it is taken as the program text. If it is a pathname, then the program text is the content of the file. The final value of the accumulator is returned." (loop with src = (if (stringp input) input (slurp input)) with accumulator = 0 for c across src do (case c (#\h (write-line "Hello, world!" out)) (#\q (write-string src out)) (#\+ (incf accumulator)) (#\9 (do ((n 99 (1- n))) ((zerop n)) (format out "~&~%~w bottle~:p of beer on the wall~%~ ~w bottle~:p of beer~%~ Take one down, pass it around~%~ ~:[~w bottle~:p~;No more bottles~] ~ of beer on the wall~%" n n (zerop (1- n)) n)) (format out "~&~%No more bottles of beer on the wall~%~ No more bottles of beer on the wall~%~ Go to the store and buy some more~%~ 99 bottles of beer on the wall.~%"))) finally (return accumulator)))