2.2.3.1 Scheme Programs

A single sentence is a simple Scheme program. For example:

> (* (+ 4 5) (- 3 2))
9

Functions may be defined as compound sentences involving the special words define and lambda. For example:

(define square
    (lambda (x)
      (* x x)))

Then

> (square 10)
100

Data is described using the special word quote as follows:

(define people
    (quote ((Clinton (president United States))
            (Dole (wanted to be President))
            (Perot (also wanted to be President)))))
> (length people)
3