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candied_orange
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Coding standard for clarity: comment every line of code?

I've worked in shops that produce life critical software and I've dealt with commenting rules that were meant to keep the code readable and potentially save lives. In my experience though the requirement becomes a brain dead chore to be ticked off of a checklist and doesn't help me stay focused on writing understandable code. It also distracts my peer reviewer from having a more meaningful conversation with me about how to make the code easier to understand.

I've also graded student code that had no comments and seen why they should be marked down for neglecting them.

I understand the idea of using good names, keeping structures simple, functions short, and modules focused will keep the code understandable enough that comments can be minimized.

I also understand that comments should explain why the code does what it does, not how.

Given all this is it even possible to write good coding standards that capture this idea? Ones that will be relevant in a peer review but won't turn into a mindless checklist activity that produces notes no more helpful than: "You forgot to comment on line 42".

An example of the kind of code this rule might require when treated as a line in a checklist:

/* Display an error message */
function display_error_message( $error_message )
{
    /* Display the error message */
    echo $error_message;

    /* Exit the application */
    exit();
}

/* -------------------------------------------------------------------- */

/* Check if the configuration file does not exist, then display an error */
/* message */
if ( !file_exists( 'C:/xampp/htdocs/essentials/configuration.ini' ) ) {
    /* Display an error message */
    display_error_message( 'Error: Configuration file not found. Application has stopped');
}

If it is possible to express this properly in a standards document, and it might simply not be, I'd like to capture an idea along the lines of: consider a comment for every line, sequence, statement, section, structure, function, method, class, package, component, ... of code. Next consider renaming and simplifying to eliminate any need for a comment so you can delete it. Check in while comments are rare. Repeat until deadline. Then repeat some more

candied_orange
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