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let vs var ks

Benchmark created by Kerri Shotts on June 3, 2017

Test runner

Ready to run.

Test Ops/sec

let

Testing in
Test	Ops/sec
let	`function foo(x) { let c = 0; for (let i = 0; i < x * 30000; i++) { c = c + x; } return c; } foo(50);`	ready
var	`function foo(x) { var c = 0; for (var i = 0; i < x * 30000; i++) { c = c + x; } return c; } foo(50);`	ready
var in fn	`function foo(x) { var c = 0; for (var i = 0; i < x * 30000; i++) { (function (i) { return c = c + x; }).call(undefined, i); } return c; } foo(50);`	ready

function foo(x) {
  let c = 0;
  for (let i = 0; i < x * 30000; i++) {
    c = c + x;
  }
  return c;
}
foo(50);

ready

var

function foo(x) {
  var c = 0;
  for (var i = 0; i < x * 30000; i++) {
    c = c + x;
  }
  return c;
}
foo(50);

ready

var in fn

function foo(x) {
  var c = 0;
  for (var i = 0; i < x * 30000; i++) {
    (function (i) {
      return c = c + x;
    }).call(undefined, i);
  }
  return c;
}
foo(50);

ready

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.

Revision 1: published by Kerri Shotts on June 3, 2017