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Orunmila

Don't make me think!

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A colleague of mine recommended this little book to me sometime last year. I have been referring to it so often now that I think we should add this to our reading list for embedded software engineers.

The book is called "Don't make me think", by Steve Krug.The one I linked below is the "Revisited" version, which is the updated version.

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This book explains the essense of good user interface design, but why would I recommend this to embedded software engineers? After all embedded devices seldom have rich graphical GUI's and this book seems to be about building websites?

It turns out that all the principles that makes a website easy to read, that makes for an awesome website in other words, apply almost verbatim to writing readable/maintainable code! 

You see code is written for humans to read and maintain, not for machines (machines prefer to read assembly or machine code in binary after all!). The principles explained in this book, when applied to your software will make it a pleasure to read, and effortless to maintain, because it will clearly communicate it's message without the unnecessary clutter and noise that we usually find in source code.

You will learn that people who are maintaining and extending your code will not be reasoning as much as they will be satisficing (yes that is a real word !). This forms the basis of what Bob Martin calls "Viscosity" in your code. (read about it in his excellent paper entitled Design Principles and Design Patterns. The idea of Viscosity is that developers will satisfice when maintaining or extending the code, which results in the easiest way to do things being followed most often, so if the easiest thing is the correct thing the code will not rot over time, on the other hand if doing the "right" thing is hard people will bypass the design with ugly hacks and the code will become a tangled mess fairly quickly. But I digress, this book will help you understand the underlying reasons for this and a host of other problems.

This also made me think of some excellent videos I keep on sending to people, this excellent talk by Chandler Carruth  which explains that, just like Krug explains in this little book, programmers do not actually read code, they scan it, which is why consistency of form is so important (coding standards). Also this great talk by Kevlin Henney which explains concepts like signal to noise ratio and other details about style in your code (including how to write code with formatting which is refactoring immune - hint you should not be using tabs - because of course only a moron would use tabs)

Remember, your code is the user interface to your program for maintainers of the code who it was written for in the first place. Let's make sure they understand what the hell it is you were doing before they break your code!

For the lazy - here is an Amazon share link to the book, click it, buy it right now!

https://amzn.to/2ZEoO4O

 

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