Nodejs Array Unique unique()

Method Source Code

// Return a unique version of an array
Array.prototype.unique = function(){
   var u = {}, a = [];
   for(var i = 0, l = this.length; i < l; ++i){
      if(u.hasOwnProperty(this[i])) {
         continue;/*w w  w .j  a  v a2 s .  c o m*/
      }
      a.push(this[i]);
      u[this[i]] = 1;
   }
   return a;
}

Related

1. unique()

   Array.prototype.unique = function() {
       var a = this.concat();
       for(var i=0; i<a.length; ++i) {
           for(var j=i+1; j<a.length; ++j) {
               if(a[i] === a[j])
                   a.splice(j, 1);
       return a;
   ...
   

2. unique()

   Array.prototype.unique = function() {
       var a = this.concat();
       for(var i=0; i<a.length; ++i) {
           for(var j=i+1; j<a.length; ++j) {
               if(a[i] === a[j])
                   a.splice(j--, 1);
       return a;
   ...
   

3. unique()

   Array.prototype.unique = function() {
     var json = {};
     var res = [];
     for(var i = 0;i < this.length;i++) {
       if(!json[this[i]]) {
         res.push(this[i]);
         json[this[i]] = 1;
     return res;
   var a = [1,2,3,3,2,1,4,4,0,7];
   console.log(a.unique());
   

4. 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;
   

5. 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;
   ...
   

6. 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;
   };
   

7. 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;
   

8. unique()

   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);
           else
               i++;
       return u;
   ...
   

9. unique()

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