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My code refactoring algorithm

Liraz Siri - Mon, 2011/05/02 - 09:26 - 5 comments | Latest by Liraz Siri

You're looking at a block of Python code. It's not immediately obvious what it does. It's sort of a mess and you realize it needs to be refactored. But how? What mental algorithm do you use?

Here's a trick I just figured out how to put into words. You first add comments to your code to make it easier to explain what it's doing in each part. Then you restructure the code until those comments are no longer necessary, using the comments as a guide to creating high level constructs that not only tuck complexity neatly away, they also explain the purpose of the surface.

What tricks do you use? 

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Comments
Guest's picture

Umh, I don't get what you

Guest - May 03 2011, Tue 06:58.

Umh, I don't get what you mean. If you always chose the right names for indentifiers and care about the common guidelines (not to much identation levels, useful sparse comments, etc) you don't need to refactor code because "readability" problems.

Liraz Siri's picture

Those are good rules of thumb

Liraz Siri - May 04 2011, Wed 03:59.
Implementing the "common guidelines" will bring you a long way, but I find that often isn't enough. The point I was trying to make is that truly readable code shouldn't need any explanation / comments. If it does, I take that as a signal that something is wrong.
Guest's picture

Finally somone actually put

Victor Fontes - May 04 2011, Wed 15:02.

Finally somone actually put that in words :)

Guest's picture

version control thinking helps

Ilya Vassilevsky - May 05 2011, Thu 00:57.

I find it useful to code when you know it is under version control. And you know you will eventually need to read patches and stuff. This makes you write shorter lines, break your expressions into more lines. This improves readability a lot.

Liraz Siri's picture

Version control essential

Liraz Siri - May 05 2011, Thu 02:29.
I started using version control about a decade ago (RCS integrated with Emacs) and found it immediately improved my productivity. By a lot. Suddenly it was much easier to spot exactly what I had changed since the last revision. Nowadays I try to make all my commits self-contained and self-documenting. Thankfully I don't use RCS any more. Git is much nicer.

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