Chapter 5


“That language is an instrument of human reason, and not merely a medium for the expression of thought, is a truth generally admitted.”

—George Boole

“The way I feel about music is that there is no right and wrong. Only true and false.”

—Fiona Apple

In this chapter:

- Boolean expressions.

- Conditional statements: How a program produces different results based on varying circumstances.

If, Else If, Else.

5.1 Boolean Expressions

What’s your favorite kind of test? Essay format? Multiple choice? In the world of computer programming, we only take one kind of test: a boolean test—true or false. A boolean expression (named for mathematician George Boole) is an expression that evaluates to either true or false. Let’s look ...

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