And your colleagues are probably correct with respect to this sort of «what it does» commenting. That can be counterproductive because if the code changes and the comment isn’t updated accordingly, it can be ambiguous. Better have the code be the singular source of truth. However, «why it does it» comments are another story and usually accepted by most as helpful.
if the code changes and the comment isn’t updated accordingly, it can be ambiguous.
People always site this as a reason comments are bad. In 30+ years as a developer I have seen (and participated in) a lot of failed software projects, but not once has a mismatch between comments and code been the actual cause of the failure. Moreover, the same logic could be applied to the names of methods and variables (“if the code changes and the method and variable names aren’t updated accordingly, it can be ambiguous”) but nobody ever suggests getting rid of that. At the end of the day, comments are useful for imparting information about the code to future developers (or yourself) that is too complicated to be adequately communicated by a method name.
I didn’t say the source of failure. I said a source of ambiguity. And having also been in the industry for decades, I have encountered it many times, where a junior programmer or somebody new to a project read some documentation and assumed a behavior which in fact did not match the current implementation. So you may have been fortunate, but your experience is certainly not ubiquitous.
With respect to variable names, I’d suggest those too should absolutely be updated too if the name is given in a way that adds ambiguity.
I’m not saying comments are bad; rather that bad comments are bad, and sometimes worse than no comment.
I’ll add that you should have a comment anytime you are using some sort of algorithm to explain what it is and the expected result when it’s not intuitive or a complex math operation that isn’t immediately clear.
Ex// I’m using Newton’s Method to approximate a solution to speed up the inverse square root
And your colleagues are probably correct with respect to this sort of «what it does» commenting. That can be counterproductive because if the code changes and the comment isn’t updated accordingly, it can be ambiguous. Better have the code be the singular source of truth. However, «why it does it» comments are another story and usually accepted by most as helpful.
People always site this as a reason comments are bad. In 30+ years as a developer I have seen (and participated in) a lot of failed software projects, but not once has a mismatch between comments and code been the actual cause of the failure. Moreover, the same logic could be applied to the names of methods and variables (“if the code changes and the method and variable names aren’t updated accordingly, it can be ambiguous”) but nobody ever suggests getting rid of that. At the end of the day, comments are useful for imparting information about the code to future developers (or yourself) that is too complicated to be adequately communicated by a method name.
I didn’t say the source of failure. I said a source of ambiguity. And having also been in the industry for decades, I have encountered it many times, where a junior programmer or somebody new to a project read some documentation and assumed a behavior which in fact did not match the current implementation. So you may have been fortunate, but your experience is certainly not ubiquitous.
With respect to variable names, I’d suggest those too should absolutely be updated too if the name is given in a way that adds ambiguity.
I’m not saying comments are bad; rather that bad comments are bad, and sometimes worse than no comment.
I’ll add that you should have a comment anytime you are using some sort of algorithm to explain what it is and the expected result when it’s not intuitive or a complex math operation that isn’t immediately clear. Ex// I’m using Newton’s Method to approximate a solution to speed up the inverse square root