Almost had to mark this one NSFW

CodexArcanum, 3 months ago

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

kevincox, 3 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, 3 months ago

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

charolastra, 3 months ago

What about figuratively?

orclev, 3 months ago

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