Boolean procedures and values

Common ways of working with truth (or truishness) and non-truth.

A

(and exp1 exp2 ... expn)— Evaluate each expression in turn until one of them returns false or we run out expressions. In the former case, returns false (#f). In the latter case, returns the value of expn.

N

(not val)— If val is false (#f), return true (#t). If val is anything else, return false.

O

(or exp1 exp2 ... expn)— Evaluate each expression in turn until one of them returns a truish value (one that is not false). Return that value. If all of the expressions return false, returns false.