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table of contents

functions
3 Let’s get organized

As programs grow, the code often becomes more complex.
And complex code can be hard to read, and even harder to maintain. One way of
managing this complexity is to create functions. Functions are snippets of code
that you use as needed from within your program. They allow you to separate out
common actions, and this means that they make your code easier to read and
easier to maintain. In this chapter, you’ll discover how a little function knowledge
can make your coding life a whole lot easier.

Starbuzz is out of beans! 78
What does the new program need to do? 79
Don’t duplicate your code... 81
Reuse code with functions 82
Always get things in the right order 84
Return data with the return command 87
Use the Web, Luke 93
The function always sends the same message 94
Use parameters to avoid duplicating functions 96
Someone decided to mess with your code 102
The rest of the program can’t see the password variable 104
When you call a function, the computer creates a fresh list of variables 105
When you leave a function, its variables get thrown away 106
Starbuzz is fully stocked! 110
Your Programming Toolbox 111

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