A comment is worth leaving. I've come round to thinking there isn't one that explains what the code does. If you need a sentence to say what a block is for, the block is telling the wrong story. Rename the function. The comment disappears because nothing needed explaining.

People hear when I say this that I want no comments at all. A comment that explains why, or cites the paper the algorithm came from, or records the incident that made this branch exist, is doing work the code cannot do. That kind of note belongs next to the module and ages fine. The one I want gone is the running narration, the line above the loop that says what the loop does. Those rot first, because the code underneath them changes and the sentence above it doesn't.

This is not a style preference. A comment is a second copy of the meaning. The code does what it does and the comment says what it used to do. The reader now has to decide which one to believe. That's worse than no explanation at all, because the wrong one is right there in the same file looking authoritative.

Agents have made me firmer on it rather than softer. A developer reading a vague function works the intent out from everything around it. An agent takes the function name and the comment at face value and builds on whichever it read last, so a lazy name becomes the vocabulary for the next twenty files. The code is the meaning because the code is what gets copied.

If the meaning isn't obvious, the move is always the same: rename the function, split it, improve the parameter names. Look again and look harder before you reach for the comment.

The full write-up is at https://prickles.org/tenet/self-documenting-code/F5

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[–] 1 point 9 hours ago

For me, the same rules apply, but as you say or hint, SQL as a language is different from higher, "structured" programming languages.

Adding comments on subqueries, applies, conditions, doing deliberate line breaks or oneliners, procedure comments and documentation where they make sense - most of the same things apply and are applicable. Structuring and commenting works quite well, until it doesn't for performance and readability reasons where you don't want to introduce additional procedures or functions or separate other aspects.

In those cases, it is what it is. Often comments can live on the lines where the aspect is.

I also like to use block comments with open and closing block indication like

-- \ Table or aspect something stuff \
[…]
-- / Table or aspect something stuff /

The language doesn't provide the structure for it, but I can still implement that structure through text comments alone.

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