Comment by KronisLV
2 months ago
How would you use good naming to explain this https://en.wikipedia.org/wiki/Fast_inverse_square_root#Overv...
Or how would you name methods and variables to explain why some payment reconciliation process skips matching for transactions under 0.50 EUR and just auto-approves them, because the external payment processor rounds differently than the internal ledger at sub-euro amounts, creating mismatches that were flooding the finance team's exception queue in 2013, explained more under Jira issue ZXSV-12456 and more details are known by j.doe@myorg.com. The threshold was chosen after analyzing six months of false positives, when it's any higher someone being undercharged doesn't get caught. I don't think autoApproveThreshold = 0.50 or anything like that would get the full context across, even if the rules themselves are all code.
I think surely you can have both! Code should explain itself as often as possible, but when you hit a wall due to some counter-intuitive workarounds being needed, or some business rules or external considerations that you need to keep track of, then comments also make sense. Better than just putting everything in a Jira issue somewhere, given that it often won't be read by you or others and almost certainly will not be read by any AI agents (unless you have an MCP or something, but probably uncommon), or spending hours trying to get the code to explain something it will never explain well. I've had people ask me about things that are covered in the README.md instead of reading it.
You’ve correctly identified that naming isn’t sufficient for all communication. Name the things that stay constant in the code and explain the things that vary with a particular implementation in version control messages. Version control as a medium communicates what context the message was written for, which is far more appropriate than comments.
> Name the things that stay constant in the code and explain the things that vary with a particular implementation in version control messages.
Then the question becomes how often we look in the version control history for the files that we want to touch.
Which of these is more likely:
A) someone digging into the full history of autoApproveThreshold and finding out that they need to contact j.doe@myorg.com or reference ZXSV-12456
B) or them just messing the implementation with changes due to not reviewing the history of every file they touch
If someone is doing a refactor of 20 files, they probably won't review the histories of all of those, especially if the implementation is spread around a bunch of years, doubly so if there are a bunch of "fixes" commit messages in the middle, merge commits and so on. I've seen people missing out on details that are in the commit log many, many times, to the point where I pretty much always reach for comments. Same goes for various AI tools and agents.
Furthermore, if you want to publish a bit of code somewhere (e.g. Teams/Slack channel, or a blog), you'd need to go out of your way to pull in the relevant history as well and then awkwardly copy it in as well, since you won't always be giving other people a Git repo to play around with.
It's not that I don't see your point, it's just that from where I stand with those assumptions a lot of people are using version control as a tool wrong and this approach neither works now, nor will work well for them in the future.
It's more or less the same issue as with docs in some Wiki site or even a separate Markdown file (which is better than nothing, definitely closer than a Wiki, especially if the audience is someone who wants an overview of a particular part of the codebase, or some instructions for processes that don't just concern a few files; but it's still far removed from where any actual code changes would be made, also a downside of ADRs sometimes).