Oh I remember what it does...I do not remember how it does.
As an undergraduate, I wondered how it was possible to write code professionally, because I could only barely fit the semester-long programming assignment in my head. When I asked my professor about it, I got an independent study credit to learn about UML.
UML (as a representative example of thoughtful documentation) is a partial answer. But actually a much larger part is that with practice I can hold a lot more code in my head. Today, that semester project seems trivial and if I see a stack trace I can tell you how to fix the bug that caused that exception to get thrown.
As a senior dev, I'd answer "how do you remember what your code does?" with
- As you work, you get better at just remembering
- As you find patterns and follow them, you'll have less to remember (I bet I know what the
downloadUnpackUpdate()method does!) - As you do the first two, you'll learn to recognize when comments are helpful
I'm still waiting for the day I see UML in a professional context. My undergrad teachers were all about it.
Similarly, I don't design software using design patterns, and I've had to discourage juniors from forcing them into projects where they don't add any value. But that's not to say design patterns aren't useful. They do exactly what you say, allowing your brain to recognise a pattern so you can remember or communicate it without having to go into details. Most of the time it won't be an exact fit for the ideal pattern implementation, but it's still easier to remember the variation.
I wish they were taught more as communication and cognitive tools than silver bullets for good software design.
In the real world there aren't even that many patterns. On a very large project you're likely to see the same patterns repeated throughout the system, because a good architecture doesn't add variation and complexity unless there's a lot of value to gain. You learn the default way, and then the diffs.
The entire purpose of writing good readable code which is mostly self-explanatory and were it isn't it's properly commented to explain what's going on, is so that it it's not a necessary for the person who picks it up later to be somebody who does remember what that code does and how it does it.
Whilst this is mainly important to allow other people to work in that code, as a side effect the actual person who wrote the code if they follow those coding principles needs not remember what it does and how it does it.
One of the upsides of being a senior dev is having figured this kind of thing out from experience, which offsets the downside that since you're older and have done a ton of things, it's less likely that you will properly remember the details of a specific code base after some months of not looking at it.
You dont. Thats why you write comments!
Code never lies; comments sometimes do.
You dont. Thats why you write code that explains itself. For higher level info you write documentation.
Yes. And also comments :-)
In a more serious note, that's why you document your software!
- encapsulation and meaningful function names.
My first tech job out of college, I was told to go talk to "Dave," the guru old-timey programmer and learn the lay of the land. He turned out to be this crotchety old guy, with low tolerance for idiots, but a soft spot for someone who actually paid attention.
A few months in, I was told to go fix a feature in the company's main product which was sold to power utilities. This was a MASSIVE code base, with a mix of C, C++, assembler, and a bit of Fortran thrown in. I spent a week poring through all the code trying to figure things out. Then I hit a mystery workflow that didn't make sense.
I walk over to Dave's office and ask a specific question. Now, mind you, he had worked on this years ago, and had long moved on to new products. He leans back in his chair, stares at the ceiling, then without looking at the screen once tells me to go look at such and such file for such and such variable, and a list of functions that were related. I go back to my desk and damn if it wasn't EXACTLY as he described.
Now, I'm probably as old as he was then. I don't remember what I wrote an hour ago. No matter what I build, I'll always be in awe of Dave and what he could keep in his head.
I wish my brain worked half as well as guys like that.
Plot twist: Dave had cheat sheets for previous projects glued to the ceiling
Alt theory: The guy you replaced failed miserably. Dave poked around but decided it wasn't worth his time fixing. Instead, decided to look badass for the cameras and died a legend.
Which is why making code readable is so very important. Our juniors and students will think we're ridiculous, when we spend a long time cleaning up some code or choosing the least misunderstandable name for a type. But you fuck that up and then others, as well as your future self, will be wasting many more minutes misunderstanding what your code does.
Readable code is especially important when companies lay people off every six months so you constantly lose expertise
I treat my future self a few months from now as a separate person who does not remember anything about why or what the specific code fragments do. And I'm grateful to my past self for doing the same.
Plus, you never know when you need to actually delegate supporting a particular piece of a solution to another person.
Write your code as if the next person that works with it is a violent psychopath who knows where you live.
Partially yes. But if I create something myself I can "revisit" the headspace of that portion very easily, like I walked into a room.
Doesn't work as well on codebases I don't own fully though.
Yeah, which is why pairing works so well. Suddenly, you've got two people who were there when it was created and might know why certain design decisions were made.
Which means twice the savings when you unexpectedly lay them both off!
This made me chortle. I remember when I first joined a dev team asking someone how many of something their section should be able to store:
I don’t know, I’d have to look at the code.
It was an eye opening moment. Very few people can keep everything in their head. I’ve met a couple. They were rockstars who were truly exceptional.
For me it all depends on how often a project changes. If it's constantly in flux, I don't bother remembering any of it because I might not be the last one who touched it. The more you try to remember everything, the more wrong you become due to the successive work of your coworkers.
The people who say "the code is the documentation" totally misunderstood what that was supposed to look like
The code is so convoluted the programmer has no idea how it works. Just tables and arrays references each other.
