; Conditionals ; ------------ ; Use the if statement to put a conditional. ; Syntax: ; (if cond [true statement] [optional false statement]) (define a 50) (define b 30) (if (< a b) (display "a is lesser than b") (display "a is not lesser than b") ) ; Note: there can only be _one_ statement in the if conditionals. If you want ; to execute more than one statement use the "begin" construct. "begin" packs ; a few statements into one statement (and returns the value of the ; last statement. (if (< a b) (begin (display a) (display " is lesser than ") (display b) (newline) ) ) ; The if returns the value of the expression that was executed. (define max-of-a-and-b (if (> a b) a b))