Example
(loop for i from 0 to 10
do (print i)) ; prints 0 1 2 3 4 5 6 7 8 9 10
(loop for i from 0 below 10
do (print i)) ; prints 0 1 2 3 4 5 6 7 8 9 10
(loop for i from 10 above 0
do (print i)) ; prints 10 9 8 7 6 5 4 3 2 1
(loop for i from 10 to 0
do (print i)) ; prints nothing
(loop for i from 10 downto 0
do (print i)) ; prints 10 9 8 7 6 5 4 3 2 1 0
(loop for i downfrom 10 to 0
do (print i)) ; same as above
(loop for i from 1 to 100 by 10
do (print i)) ; prints 1 11 21 31 41 51 61 71 81 91
(loop for i from 100 downto 0 by 10
do (print i)) ; prints 100 90 80 70 60 50 40 30 20 10 0
(loop for i from 1 to 10 by (1+ (random 3))
do (print i)) ; note that (random 3) is evaluated only once
(let ((step (random 3)))
(loop for i from 1 to 10 by (+ step 1)
do (print i))) ; equivalent to the above
(loop for i from 1 to 10
for j from 11 by 11
do (format t "~2d ~3d~%" i j)) ;prints 1 11\n2 22\n...10 110
