Comment by twii

No, it's not a joke. A junior dev can read this code and it will be very hard to create bugs.

Inlining with arrows is just a more functional approach, as I would write in Coffee:

  exists filename, (fileExists) -> handleFile filename, fileExists

Anything wrong with that line of code?

I just try very hard to keep my code as simple as possible.

I hope you know it's trivial to write a log function that accepts different callees so you end up with only 1 'if (err)'.

I didn't test, but I wouldn't be surprised if my example runs times faster as well btw.