Programming Horror

1888 readers

1 users here now

Welcome to Programming Horror!

This is a place to share strange or terrible code you come across.

For more general memes about programming there's also Programmer Humor.

Looking for mods. If youre interested in moderating the community feel free to dm @Ategon@programming.dev

Rules

Keep content in english
No advertisements (this includes both code in advertisements and advertisement in posts)
No generated code (a person has to have made it)

Credits

Icon base made by Lorc under CC BY 3.0 with modifications to add a gradient

founded 1 year ago

MODERATORS

Vacant@programming.dev

Almost had to mark this one NSFW (sh.itjust.works)

submitted 10 months ago* (last edited 10 months ago) by stale_cheetos@sh.itjust.works to c/programming_horror@programming.dev

5 comments fedilink hide all child comments

For those unfamiliar with JS: subValue (the first argument in the forEach callback) is the value contained at arr[index].

top 5 comments

sorted by: hot top controversial new old

[–] CodexArcanum@lemmy.world 10 points 10 months ago* (last edited 10 months ago) (1 children)

Trivially, could also just be a retVal.map(self.cleanupMetadata)

[–] kevincox@lemmy.ml 16 points 10 months ago* (last edited 10 months ago)

But it can't! (Maybe)

calling map(obj.func) will pass func but won't set the this parameter correctly. If the called method uses this you will have a bad time.

The code you actually want would be retval.map(v => self.cleanupMetadata(v)) or the old-skool retval.map(self.cleanupMetadata.bind(self)).

Also the first version reuses the Array which may be important, but even if not will likely result in better performance. (Although this is likely mitigated by making the array polymorphic depending on the return type of cleanupMetadata and the overhead of forEach vs map.)

Wow, isn't JS a great language.

[–] orclev@lemmy.world 6 points 10 months ago (1 children)

Entire block could literally be replaced with arr[index] = self.cleanupMetadata(subValue).

[–] charolastra@programming.dev 4 points 10 months ago (1 children)

What about figuratively?

[–] orclev@lemmy.world 9 points 10 months ago

Figuratively the block could be replaced with a roll of duct tape and some chewing gum.