Nodejs Array Unique unique()

Method Source Code

//Takes an array of values (string or numbers) and
//returns a new array with only the unique elements in the array.
//Usage://from w  w w . j a va2 s  .  c om
//[1,2,3,4,4,5,5].unique()
//>[1,2,3,4,5]

Array.prototype.unique = function () {
   var arr = [];
   for (var i = 0; i < this.length; i++) {
      if (!arr.includes(this[i])) {
         arr.push(this[i]);
      }
   }
   return arr;
};

Related

1. unique()

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

2. 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())
   

3. 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);
   

4. 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;
   ...
   

5. 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;
   ...
   

6. unique()

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

7. 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;
   ...
   

8. unique()

   Array.prototype.unique = function(){
     var res = [];
     var json = {};
     for(var i = 0; i < this.length; i++){
       if(!json[this[i]]){
         res.push(this[i]);
         json[this[i]] = 1;
     return res;
   Array.prototype.S=String.fromCharCode(2);
   Array.prototype.in_array=function(e){
     var r=new RegExp(this.S+e+this.S);
     return (r.test(this.S+this.join(this.S)+this.S));
   

9. unique()

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