Nodejs Array Unique uniq()

Method Source Code

Array.prototype.uniq = function() {
   var results = [];
   for (var i = 0, len = this.length; i < len; i++) {
      var found = false;
      for (var j = 0, len2 = results.length; j < len2; j++) {
         if (this[i] === results[j]) {
            found = true;/*  w  w w  .  j  a  v a 2s  .  c om*/
            break;
         }
      }
      if (!found) {
         results.push(this[i]);
      }
   }
   
   return results;
};

// refactored
Array.prototype.uniq = function() {
   var results = [];
   for (var i = 0, len = this.length; i < len; i++) {
      if (results.indexOf(this[i]) < 0) {
         results.push(this[i]);
      }
   }
   
   return results;
};

// refactored (requires Enumerable)
Array.prototype.uniq = function(sorted) {
   return this.inject([], function(array, value, index) {
      if (0 == index || (sorted ? array.last() != value : !array.include(value))) {
         array.push(value);
      }
      
      return array;
   });
};

Related

1. uniq()

   Array.prototype.uniq = function () {
     var arr = [];
     var flag = true;
     this.forEach(function (item) {
       if (item != item) {
         flag && arr.indexOf(item) === -1 ? arr.push(item) : '';
         flag = false;
       } else {
         arr.indexOf(item) === -1 ? arr.push(item) : ''
   ...
   

2. uniq()

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

3. uniq()

   Array.prototype.uniq = function () {
     const uniqArr = [];
     for (let i = 0; i < this.length; i++) {
       if (!uniqArr.includes(this[i])) {
         uniqArr.push(this[i]);
     return uniqArr;
   };
   ...
   

4. uniq()

   Array.prototype.uniq = function() {
     var uniq_array = [];
     for (var i=0; i<this.length; i++) {
       curr_ele = this[i]
       if (this.lastIndexOf(curr_ele) === i) {
         uniq_array.push(curr_ele);
     return uniq_array;
   ...
   

5. uniq()

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

6. uniq()

   Array.prototype.uniq = function () {
     var occurrenceHash = {};
     var result = [];
     for (var i = 0; i < this.length; i++) {
       if (!occurrenceHash[this[i]]) {
           occurrenceHash[this[i]] = true;
           result.push(this[i]);
     return result;
   

7. uniq()

   Array.prototype.uniq = function () {
     var results = [];
     for (var i = 0; i < this.length; i++) {
       var includes = false;
       for (var j = 0; j < results.length; j++) {
         if (results[j] === this[i]) {
           includes = true;
       };
   ...
   

8. uniq()

   Array.prototype.uniq = function ()
     var dups = [];
     for (var i = 0; i < this.length; i++)
       var flag = true;
       for (var j = 0; j < dups.length; j++)
         if (this[i] === dups[j])
   ...
   

9. uniq()

   Array.prototype.uniq = function () {
       var flag = false;
       var result = [];
       for(var i=0;i<this.length;i++) {
           if(result.indexOf(this[i]) == -1) {
               if(this[i]==this[i]) {
                   result.push(this[i]);
               else if(!flag) {
   ...