One of the benefits of using modern editors is that it's really easy to navigate your code base. If you're looking at a method call, for example, you can use a keystroke combination to jump to the method definition.
But there's a drawback to this.
If you're not careful, as you add new code you can end up with monster methods, or monster-sized classes. Let me ask you this - what do you think the maximum size of a class should be? 100 lines? 500 lines? 10,000 lines? While we won't agree on an exact number, we can all agree that a class with 10,000 lines in it is much more likely to have bugs in it than one with 100 lines.
But no one sets out to write such a huge class. How does it get this way? Simple - over time, various people make little modifications to a class. How many times have you looked at a modification and thought to yourself, "Perfect, I'll just add these lines of code here, and it'll support the new feature." After enough people do that, your 500 line class grows and grows. And grows!
Here's a fairly innocuous bit of code. If I had just added this, without line numbers being displayed, I might not realize how big the class already is. But, as the screen shot on the right shows, I might be more inclined to realize that I shouldn't grow this class any further since it already has nearly 20,000 lines of code in it!
| No Line Numbers |
Line Numbers show a problem! |
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Thus, my advice: turn on line number display in your editor. In Visual Studio, turn on Line Numbers by going to Tools | Options | Text Editor and check Line Numbers
Now, when you're fixing bugs or adding features, you'll see line numbers. And when you get near the bottom of a file, you'll have another reminder that the class is growing out of control. Then you can plan some refactoring to break up the monster method or class. And improve your code base.
Turn on line numbers in your editor. They're an early warning system.