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CS253 Helper Classes

Helper Classes

• C programmers create helper functions
• C++ programers create helper classes

If your class has to do several things, then it may help to break it down into smaller classes.

We didn’t evolve to do object-oriented programming. Our brains aren’t designed to do this sort of thing. They’re not very good at it. Therefore, keep each class simple & managable.

Example

Consider a container that is a hash table using filesystem storage. It may be useful to create a smaller class that stores a single item in the filesystem. Now, create a hash table class that stores the filesystem objects.

You can debug each class separately, and each class does only one thing. The filesystem class doesn’t know anything about hashing, and the hash table class doesn’t know anything about filesystems.

Objections

“I can understand this class just fine. Is it too complex for you ?”

• Gosh, aren’t you masculine. 🕱♂
• Making things deliberately more difficult, just to prove that you can do it, is a fine attitude for weight-lifting, but not for programming.
• Especially not for code which is likely to be maintained by others, so … all code.

Objections

“Having two classes will increase overhead.”

• May I see your profiling data? Oh, you don’t have any? Yeah, I thought so.
• Your intuition is a poor guide, here.
• Also, having separate classes will decrease program development time and maintenance costs.
• Engineering delays are orders of magnitude more important than a few microseconds of function call overhead.

Objections

“You expect me to write two classes!?”

• If you separate the functionality, then two classes are easier to write than one overblown monster of a class.
• Do you make gigantic run-on paragraphs because the overhead of actually starting a new sentence with the period and the capital letter and the agony of deciding whether to type one space or two is too much for you and therefore you “save time” by never breaking your paragraph up into sentences which would not only help you as the author break up your thoughts into manageable and orderly components but also help the poor reader by making the input bite-sized and flowing in an sensible fashion and therefore cost the reader a vast amount of time by making them reread the same enormous paragraph several times in a vain attempt to comprehend it while cursing the writer to the flames of perdition?

Alternatives

If you’re afraid of writing classes, then look for a new profession. There are so many!