Even when I have no issues with the precedence order, I often add parens anyway because it helps with mental grouping at a glance, instead of having to scan and mentally parse the line.
As a young egotist I would often omit parens in complicated C expressions. I did this intentionally and in a very self-satisfied way - writing multi-line conditionals and lining them up neatly without parens with a metaphorical flourish of my pen.
Then one day, chasing a hard-to-find bug, I realised it had happened because I'd mixed up the precedence of && and || in a long conditional. I was an idiot. Since then I've made a point of reminding myself that I know nothing and that there's nothing to be gained from pretending I do, and putting parens in everywhere.
Sometimes, even now, I get those grandiose moments when I think the code I'm writing cannot possibly go wrong. Those are the moments that call for a bit of fresh air and an extra unit test or two.
That's a great observation. Passing on that expertise is what wizened veterans can do to move our capabilities along and not let learning go to waste. I've heard that a big reason for sometimes struggling software engineering quality in countries and companies is places where the only way to grow is to become a manager - you need people to stay in technical paths so they can pass on that learned knowledge.
Exactly this. I add parenthesis not for computer but for myself. Mostly because it is easier to comprehend. I think the reason for this is that I learned precedence order something like 25 years ago in fifth grade maths and still do it to this day.
