Nodejs Array Unique unique()

Method Source Code

Array.prototype.unique = function(){
  'use strict';/* w  ww .ja v  a2s  .co  m*/
  var im = {}, uniq = [];
  for (var i=0;i<this.length;i++){
    var type = (this[i]).constructor.name, 
    //          ^note: for IE use this[i].constructor!
        val = type + (!/num|str|regex|bool/i.test(type) 
               ? JSON.stringify(this[i]) 
               : this[i]);
    if (!(val in im)){uniq.push(this[i]);}
    im[val] = 1;
  }
  return uniq;
}

Related

1. unique()

   Array.prototype.unique = function() {
     var res = [this[0]];
     for (var i = 1; i < this.length; i++) {
       var repeat = false;
       for (var j = 0; j < res.length; j++) {
         if (this[i] == res[j]) {
           repeat = true;
           break;
       if (!repeat) {
         res.push(this[i]);
     return res;
   var arr = ['h', 'e', 'l', 'l', 'o', ' ', 'w', 'o', 'r', 'l', 'd', '!'];
   console.log(arr.unique())
   

2. unique()

   Array.prototype.unique = function () {
       var results  = this.sort();
       for ( var i = 1; i < results.length;i++) {
          if (results[i] === results[i-1]) {
              results.splice(i--,1);
       return results;
   

3. unique()

   Array.prototype.unique = function() {
       return this.reduce(function(accum, current) {
           if (accum.indexOf(current) < 0) {
               accum.push(current);
           return accum;
       }, []);
   function sleep(milliseconds) {
   ...
   

4. unique()

   Array.prototype.unique = function(){
     var n=[];
     this.forEach(function(v){if(!n.inArray(v)){n.push(v);}});
     return n;
   };
   

5. unique()

   var nums =[{name: 1, val: 1},
   {name: 2, val: 1},
   {name: 3, val: 2},
   {name: 4, val: 2}];
   Array.prototype.unique = function() {
       return this.reduce(function(accum, current) {
           if (accum.indexOf(current) < 0) {
               accum.push(current);
           return accum;
       }, []);
   var newArr = [];
   for (var i = 0; i < nums.length; i++) {
     newArr.push(nums[i].val);
   };
   console.log(newArr.unique());
   

6. unique()

   Array.prototype.unique = function () {
       var r = new Array();
       o:for(var i = 0, n = this.length; i < n; i++)
         for(var x = 0, y = r.length; x < y; x++)
           if(r[x]==this[i])
              continue o;
   ...
   

7. unique()

   Array.prototype.unique = function() {
     var solution = [];
     for(var i=0; i<this.length; i++) {
       if(solution.indexOf(this[i]) === -1) solution.push(this[i]);
     return solution;
   };
   

8. unique()

   Array.prototype.unique = function() {
     var arr = [this[0]];
     for (var i = 1; i < this.length; i++) {
       if ( arr.indexOf (this[i]) === -1) {
         arr.push(this[i]);
     return arr;
   var arr = [1, 2, 1, 3, 5, 3, 5, '5'];
   console.log(arr.unique());
   console.time();
   var unique2 = function(arr) {
     var 
       ary = [],
       i = 0,
       key;
     for (; key = arr[i++]; ) {
       if ( ary.indexOf(key) === -1 ) {
         ary.push(key);
     return ary;
   console.log(unique2(arr));
   console.timeEnd();
   

9. unique()

   Array.prototype.unique = function () {
       var r = new Array();
       o:for(var i = 0, n = this.length; i < n; i++)
           for(var x = 0, y = r.length; x < y; x++)
                   if(r[x]==this[i])
                           continue o;
   ...