16.4.13 Iteration

When you want to do something repeatedly, it is sometimes more natural to use iteration than recursion. A typical case for iteration is to generate some sort of table. This function:

(defun show-squares (start end)
  (do ((i start (+ i 1)))
      ((> i end) 'done)
    (format t "~A ~A~%" i (* i i))))

prints out the squares of the integers from start to end.

• do Macro