Variable Argument Lists

We have already seen several functions that can take a variable number of arguments, such as + or min. Some Lisp implementations allow such an argument list to be specified using dot notation.

(define (min1 n . others) (min1b n others))
(define (min1b n others)
  (if (null? others)
      (min1b (if (< (car others) n)
                 (car others)
             (cdr others)) ) )

> (min1 0) 0

> (min1 17 22 4 37 99 2 55) 2

In the function min1, the variable n is bound to the first argument, while others is bound to a list of the remaining arguments. min1 calls a tail-recursive function min1b to do the work.

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