Nodejs Array Unique unique()

Method Source Code

Array.prototype.unique = function() {
    var u = this.concat().sort();
    for (var i = 1; i < u.length; ) {
        if (u[i-1] === u[i])
            u.splice(i,1);/*  w  ww .  java 2s  .  co  m*/
        else
            i++;
    }
    return u;
}
var uniq = [1, 2, 3, "a", "b", "c", 2, 3, 4, "b", "c", "d"].unique();

Related

1. unique()

   Array.prototype.unique = function(){
       var u = {}, a = [];
       for(var i = 0, l = this.length; i < l; ++i){
           if(u.hasOwnProperty(this[i])) {
               continue;
           a.push(this[i]);
           u[this[i]] = 1;
       return a;
   

2. unique()

   Array.prototype.unique = function () {
       var exist = {},
           i;
       for (i = 0; i < this.length; i++) {
           if (exist[this[i]]) {
               this.splice(i, 1);
               i -= 1;
           } else {
               exist[this[i]] = true;
   ...
   

3. unique()

   Array.prototype.unique = function(){
      var u = {}, a = [];
      for(var i = 0, l = this.length; i < l; ++i){
         if(u.hasOwnProperty(this[i])) {
            continue;
         a.push(this[i]);
         u[this[i]] = 1;
      return a;
   

4. unique()

   Array.prototype.unique = function(){
     var new_array = [];
     var index = 0;
     var value = null;
     for( count=0; count < this.length; count++){
       value = this[count];
       if( new_array.indexOf(value)==-1 ){
         new_array[index++] = value;
     return new_array;
   };
   

5. unique()

   Array.prototype.unique = function () {
       var arrVal = this;
       var uniqueArr = [];
       for (var i = arrVal.length; i--; ) {
           var val = arrVal[i];
           if ($.inArray(val, uniqueArr) === -1) {
               uniqueArr.unshift(val);
       return uniqueArr;
   

6. unique()

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

7. unique()

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

8. unique()

   Array.prototype.unique = function()
       var tmp = {}, out = [];
       for(var i = 0, n = this.length; i < n; ++i)
           if(!tmp[this[i]]) { tmp[this[i]] = true; out.push(this[i]); }
       return out;
   var a = [1,2,2,7,4,1,'a',0,6,9,'a'];
   var b = a.unique();
   console.log(a);
   console.log(b);
   

9. unique()

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