Conditional Expressions and Functions

For many problems, computer programs must deal with different situations in different ways. A game program may have to determine whether an object's speed is in some range or whether it is located in some specific area of the screen. For an engine control program, a condition may describe whether or when a valve is to be opened. To deal with conditions, we need to have a way of saying a condition is true or false; we need a new class of values, which, by convention, are called BOOLEAN (or truth) values. This section introduces booleans, expressions that evaluate to Booleans, and expressions that compute values depending on the boolean result of some evaluation.

• Booleans and Relations
• Functions that Test Conditions
• Conditionals and Conditional Functions
• Designing Conditional Functions