this post was submitted on 31 Jul 2023
48 points (96.2% liked)
Programming
17377 readers
163 users here now
Welcome to the main community in programming.dev! Feel free to post anything relating to programming here!
Cross posting is strongly encouraged in the instance. If you feel your post or another person's post makes sense in another community cross post into it.
Hope you enjoy the instance!
Rules
Rules
- Follow the programming.dev instance rules
- Keep content related to programming in some way
- If you're posting long videos try to add in some form of tldr for those who don't want to watch videos
Wormhole
Follow the wormhole through a path of communities !webdev@programming.dev
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
Self-documenting code only documents what the code does, not why it does it. I can look at a well written method that populates a list with random elements from another list and go "I know what that does!" but reading the code doesn't tell me the reason this code was written or why alternatives weren't chosen.
In the case of Rust, it goes even a step further when working with unsafe code. Sure I know what invariants need to be held for unsafe code to be sound, but not everyone does, and it isn't always clear why a particular assumption made in an unsafe block (the list has at least 5 elements, for example) can be made soundly.
This is my issue with "it's self documenting code!". I'm a maintenance coder. I deal with people's code long after they're dead (or ragequit). Some are for control systems.
if (waterPressure_psi > 500) raise PipeMayBurstException
. Okay, we're dealing with water pressure, in psi unit, and if it's too high, it may break the piping. Self documenting!!Except that our pipes are rated for 1000psi. SO WHY THE 500?! Do we have one or two sites - out of hundreds - with lower rated pipes? I can double performance if we raise the threshold to 700, well within the safety tolerance, but AM I GONNA KILL SOMEONE when they upgrade to our latest controller??
Ugh, a Magic String (I call it that whatever the type)
Obviously it should really pull from facility management, but that's a bunch of moving parts where a constant is how you'd prefer the code to work
Tbh it starts to look better to just define a constant and comment it.
Well..
if (waterPressure > MAX_PRESSURE_BEFORE_YOU_FLOOD_THE_WHOLE_TOWN_OF_IPSWICH_AND_CALNE)
is pretty self-documenting. No comments needed.Although a bit long, I do like this almost impossible to ignore example of self documenting code :)