anchor.diff:              (dolist (element (aref arrs 0))
                 ((@ result-array push) (fun element)))
               (dotimes (i (length (aref arrs 0)))
  -              (let ((args-array (mapcar (lambda (a) (return (aref a i))) arrs)))
  +              (let ((args-array (mapcar (lambda (a) (aref a i)) arrs)))
                   ((@ result-array push) ((@ fun apply) fun args-array)))))
  -        (return result-array)))
  +        result-array))
   
       (defun map-into (fn arr)
         "Call FN on each element in ARR, replace element with the return value."
  
positive.code:         (dolist (el arr)
            (setf (aref result idx) (fn el))
            (setf idx (1+ idx)))
          (return result)))
  
      (defun member (item arr)
        "Check if ITEM is a member of ARR."
        (dolist (el arr)
          (if (= el item)
              (return true)))
        (return false))
  
      (defun set-difference (arr arr-to-sub)
        "Return a new array with only those elements in ARR that are not in ARR-TO-SUB."
  
negative.code:           (unless (member el arr-to-sub)
              (setf (aref result idx) el)
              (setf idx (1+ idx))))
          result))
  
      (defun reduce (func list &optional init) ;; the use of init here is actually a bit broken wrt null
        (let* ((acc))
          (do* ((i (if init -1 0) (1+ i))
                (acc (if init init (elt list 0)) (func acc (elt list i))))
               ((>= i (1- (length list)))))
          acc))
  
      (defun nconc (arr &rest arrs)
      (when (and arr (> (length arr) 0))
  