Remove duplicates from js array (ES5/ES6)

uniq.js

var uniqueArray = function(arrArg) {
  return arrArg.filter(function(elem, pos,arr) {
    return arr.indexOf(elem) == pos;
  });
};

var uniqEs6 = (arrArg) => {
  return arrArg.filter((elem, pos, arr) => {
    return arr.indexOf(elem) == pos;
  });
}

var test = ['mike','james','james','alex'];
var testBis = ['alex', 'yuri', 'jabari'];
console.log(uniqueArray(test.concat(testBis)));

const deduplicateArrays = ( arr1, arr2 = [] ) => [
...new Set([
           ...arr1.map(i => JSON.stringify(i)),
           ...arr2.map(i => JSON.stringify(i))
          ])
].map(i => JSON.parse(i))

Hi @gevera
Beware of problems when using JSON.stringify and JSON.parse with:

• number: https://github.com/josdejong/lossless-json
• date: https://stackoverflow.com/questions/31096130/how-to-json-stringify-a-javascript-date-and-preserve-timezone

Being bitten more than once... 🤕