Custom Iterator for Number Prototype in JS

Recently I learned about JS iterators, beeing used in a for( of ) loops. Since in JS even primitives have a prototype, I wondered if it is possible to extend the Number prototype so that the following would be a valid expression:

for(let i of 10) console.log(i); //0 1 2 3 4 5 6 7 8 9

Obviously this would only work for integers, but is there a way to implement this?

Hopefully there is, but I wasn't able to create this myself since I'm new to this part of JS...

Sure, just define Number.prototype[Symbol.iterator]:

Number.prototype[Symbol.iterator] = function() {
  let currentNum = 0;
  return {
    next: () => (
      currentNum == this
      ? { done: true }
      : {
        value: currentNum++,
        done: false
      }
    )
  }
}
for (const i of 10) console.log(i);

But mutating the built-in objects (like the global Number) is very bad practice - it would be better to find another way to do whatever you're trying to accomplish, if at all possible.