Thread by @__mharrison__

This tweet obviously resonates with many.

I often get asked about debugging when teaching a course...

A 🧵

https://twitter.com/jcsrb/status/1392459191353286656

Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it.

-Kernighan's Law

🤯

When I teach programming, I emphasize that to me, the most important part is that the code is "readable."

You write code (once or twice), but it is read all the time. Optimize for what happens a lot.

Not:

😦 Brevity
😦 Cleverness
😦 Using all of the features

At some point, we will need to start debugging. This is a skill that young kids can master. (My daughter typoed some code last night and was able to fix it)

Here are my debugging tips:

💪 Prepare
💪 Use "print" debugging
💪 Rubber duck it 🦆
💪 Sleep on it
💪 Debugger
💪 Simplify/Test

Prepare - Make sure you know what you are trying to do. Read the documentation before diving in. Many problems I see are syntax errors. (See tweet above)

Print debugging - I use this all the time. Programming genius I know also use it. You can bend this into logging for production debugging.

Rubber duck - It turns out that you use a different portion of your brain when you vocalize your problems. Often times in the middle of describing it, you know your misstep.

This is called "rubber duck" debugging because people will speak to an inanimate object to get advice. The important part is to say it OUT LOUD (From "The Pragmatic Programmer")

Sleep on it - Another brain hack is called "incubation". I've slept on problems multiple times and woken up knowing what to do. Your brain will churn on issues even when you step away.

This is why pulling all-nighters trying to fix things is a misguided approach.

Debugger - A tool that allows for breakpoints and inspecting code can be useful. However, I find that the above steps often work before that.

Simplify/Test - "It works for me" is frustrating. You need to come up with the most simple version of the problem sometimes to get help. Writing tests can aid in this (and protect from future problems).

🙏 Thanks for reading!

What is your favorite advice for debugging?

Follow me for more programming-related tips.