Question

This refuses to compile. Commenting out the (setf roll line lets it compile. However, (setf roll... itself evaluates correctly in the REPL.

Program:

;; loop n times
; sum up number of hits over value v
(defun num-hits (n v)
  (let 
     ((roll)
       (table))
    (setq table (make-hash-table))
    ;;until i == n
    (loop for i from 1 to n
      (setf roll (rolld6))
;     (if (nilp (view_hash table))
;         (oxuassign_hash table roll 1)
;       (assign_hash table (+ 1 (view_hash table roll))))
      )
    (+ (view_hash table 5) (view_hash table 6))))

Message:

*** - LOOP: illegal syntax near (SETF ROLL (ROLLD6)) in (LOOP FOR I FROM 1 TO N (SETF ROLL (ROLLD6)))

Answer 1

The loop macro requires “do” before the loop body. You have

(loop for i from 1 to n
   (stuff)

and you need

(loop for i from 1 to n do
   (stuff))