Looking at old code can be an uncomfortable, embarrassing, or infuriating experience. And that's a good thing.
If you've been writing code long enough, you know the feeling of looking at old code. It's embarrassing.
(I wrapped a 20-line method in an if statement instead of using an exit clause? WTF!? What a loser!)
This feeling of embarrassment of old cold—of frustration with your past self for the decisions you made—is absolutely crucial to your development as a developer. The uncomfortable feeling that comes with looking at old code—or, worse, having to work with it—means you're getting better at writing code.
With a little help from my friend, the transitive property, that means that if you look at old code and you don't mind it—or worse, you think it's good—one of these conditions must be true:
In reality, there's always room to be a better developer if you give it the time and attention it requires.
So, take comfort in the uncomfortable feeling of looking at old code. It means the code you're writing today is better.
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