Hacker News Reader

Comment by parhamn | Hacker News Reader

This isn't true outside the theoretical best case. Definitely not true in most interpreted languages. Consider the performance difference of .reverse() (in-place or copy) vs using a descending for loop. Generally with interpreter chaining there are more "hidden" allocations/operations.

View on HN

You're comparing apples and oranges. Of course modifying an array or copying it takes way more time than looping. The comparison was not about that, it's about one loop with 10 instructions VS 10 loops each with a single instruction, for the exact same instructions.

There's no way to do this (a single instruction loop vs 10 loops with a single instruction) in JS or Golang.

I don't mean assembly-level instructions, just general instructions in the language:

  for i := range arr {
    foo1(arr[i])
    ...
    foo10(arr[i])
  }

  for i := range arr {
    foo1(arr[i])
  }
  ... 
  for i := range arr {
    foo10(arr[i])
  }

Reply on news.ycombinator.com