Learning About Debugging

I was reading a Reddit post on how Guido van Rossum stated he wanted to make Python work faster when I came across a comment chain where somebody joked that you can make any program faster by using fewer print() statements. A reply quipped “How else am I supposed to debug my programs?”. I’m assuming it was a joke for them, but this is certainly a weakness on my part. Since I’m self-taught, I find myself using standards that make sense to me, but would be bad practice for a formally taught individual. In this case, that’s using the print() statement to help me debug by running the program and seeing what I end up with, tweaking that, running it again, and so on.

The Reddit thread includes a comment chain where somebody jokes about using fewer print() statements.

Fortunately, though, somebody in the replies provided a serious answer to the quip: debuggers and logging. Because I use Linux, I’ve gotten quite familiar with log files – any time something doesn’t work, you have to check a log file to see where the problem lies. Without log files, you’re utterly confused; with log files, you’re a quick Internet search away from your answer. However, I never applied logging in my own programs. Firstly, they’re often so small that they’re easy to review without a log file; secondly, I just didn’t know how. It’s still bad practice, though.

Fortunately, one person linked to a really solid explanation of how debuggers work from last year’s PyCon:

A video by Nina Zakharenko explaining debugging in Python

It was so enlightening to watch – she described exactly how I muck around debugging my programs, using print() statements to analyze my output, adjusting it, and so on. Clearly, my bad habit was a common amateur move that happened often enough for her to be motivated to tell people about this debugger. Not only does it look like a good habit to build, the way she explains it makes it just so easy that I don’t see why I never bothered to use it in the first place.