Benchmark: Distinct - MeasureThat.net

Script Preparation code:

var myArray = ['a', 1, 'a', 2, '1'];

function onlyUnique(value, index, self) {
  return self.indexOf(value) === index;
}

Tests:

ECMAScript 5
// usage example: var unique = myArray.filter(onlyUnique).length;
With ES6 it
var unique = myArray.filter((v, i, a) => a.indexOf(v) === i).length;
ES6 has a native object Set to
let unique = new Set(myArray).size;

Rendered benchmark preparation results:

Previous results

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Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.0.0 Safari/537.36

Browser/OS: Chrome 103 on Windows

Distinct (version: 0)