racket Getting started with racket Simple Recursive Function Definition
Example
In Racket, we use recursion very frequently. Here is an example of a function that sums all of the numbers from zero to the parameter, n.
(define (sum n)
(if (zero? n)
0
(+ n (sum (sub1 n)))))
Note that there are many helpful convenience based functions used here, such as zero? and sub1. Each respectively does just what you might expect: zero? returns a boolean which says whether the given number was equal to zero, and sub1 subtracts one from its argument.
