Chapter 7. Programming Fundamentals, Part II


  • How control structures make decisions

  • How to define functions

  • Where to initialize variables efficiently

  • What those darned curly braces are all about

  • The basics of data arrays

Your tour of programming fundamentals continues in this chapter with subjects that have more intriguing possibilities. For example, I show you how programs make decisions and why a program must sometimes repeat statements over and over. Before you're finished here, you also will learn how to use one of the most powerful information holders in the JavaScript language: the array.

Decisions and Loops

Every waking hour of every day, you make decisions of some kind; most of the time, you probably don't even realize it. Don't think so? Well, look at the number of decisions you make at the grocery store, from the moment you enter the store to the moment you clear the checkout aisle.

No sooner do you enter the store than you are faced with a decision. Based on the number and size of items you intend to buy, do you pick up a hand-carried basket or attempt to extricate a shopping cart from the metallic conga line near the front of the store? That key decision may have impact later, when you see a special offer on an item that is too heavy to put in the handbasket.

Next, you head for the food aisles. Before entering an aisle, you compare the range of goods stocked in that aisle with items on your shopping list. If an item you need is likely to be found in this aisle, ...

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