Discussion on: How many ways iterate the objects and arrays in javascript?

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Replies for: Nuh-uh, bronathan! In fact, I assume that the logic / base case of the handling is void-returning. The return here is purely to opt in to tail call...

Your misunderstanding might be resolved if you take the following as an example:

const array = new Array();
array.length = 1/0;
...

An extreme example, I concede, but as an exercise, you can try to figure out the call stack sizes for different JS engines (and AFAIK they're all smaller than the maximum number the 52bit mantissa of a Number can store).

Mihail Malo • Feb 14 '19 • Edited

Optimized tail calls don't grow the stack.

They're implemented with a goto, it's basically a loop.


{
  let i = 0
  const rec = () => (i++, rec())
  try {
    rec()
  } catch {}
  console.log(i)
}

On most browsers this will give you a number.
On Safari, Mobile Safari, and some embeddable runtimes like latest Duktape It will be an infinite loop.