https://minds.md/zakirullin/cognitive
There are so many buzzwords and best practices out there, but let's focus on something more fundamental. What matters is the amount of confusion developers feel when going through the code.
Confusion costs time and money. Confusion is caused by high cognitive load. It's not some fancy abstract concept, but rather a fundamental human constraint.
Cognitive load is how much a developer needs to think in order to complete a task.
When reading code, you put things like values of variables, control flow logic and call sequences into your head. The average person can hold roughly four such chunks in working memory. Once the cognitive load reaches this threshold, it becomes much harder to understand things.
Let's say we have been asked to make some fixes to a completely unfamiliar project. We were told that a really smart developer had contributed to it. Lots of cool architectures, fancy libraries and trendy technologies were used. In other words, the author had created a high cognitive load for us.
Cognitive Load
We should reduce the cognitive load in our projects as much as possible.
Intrinsic - caused by the inherent difficulty of a task. It can't be reduced, it's at the very heart of software development.
Extraneous - created by the way the information is presented. Caused by factors not directly relevant to the task, such as smart author's quirks. Can be greatly reduced. We will focus on this type of cognitive load.
Intrinsic vs Extraneous
if val > someConstant // 🧠+
&& (condition2 || condition3) // 🧠+++, prev cond should be true, one of c2 or c3 has be true
&& (condition4 && !condition5) { // 🤯, we are messed up by this point
...
}