> I disagree that the status quo is “one error per module or per library”. It is the most common approach, hence, status quo. > I create one error type per fu

> I disagree that the status quo is “one error per module or per library”. It is the most common approach, hence, status quo. > I create one error type per function/action. I discovered this here on HN after an article I cannot find right now was posted. I like your approach, and think it's a lot better (including for the reasons described in this article). Sadly, there's still very few of us taking this approach.