JSFiddle - React, Tailwind, and code Playground

by jmd386

JavaScript

function myFunction() {
  let sum = 0;
  {
    let arr = [];
    // fill array with data
    // possibly from a JSON file or an AJAX request, or a for loop in this case
    for (let i = 0; i < 1000000; i++) {
      arr[i] = i;
    }
    for (let i = 0; i < arr.length; i++) {
      sum += arr[i];
    }
  }
  //console.log(arr); // undefined, no longer in memory!
  // do something with sum
  console.log(sum);
}
myFunction();