Check out example codes for "for in ts". It will help you in understanding the concepts better.

Code Example 1

for (let entry of someArray) {
  console.log(entry); // 1, "string", false
}

var numbers = [1, 2, 3];
for (var _i = 0; _i < numbers.length; _i++) {
  var num = numbers[_i];
  console.log(num);
}

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