Nodejs Array Flatten flatten()

Method Source Code

Array.prototype.flatten = function(){
    var flattenArray = [];
    for (var el in this) {
        var currElement = this[el];
        if (Object.prototype.toString.call(currElement) === '[object Array]' ) {
            for (var i in currElement) {
                flattenArray.push(currElement[i]);
            }/*from   ww  w.j a v a2 s  .com*/
        } else {
            flattenArray.push(currElement);
        }
    }
    deleteFunctions(flattenArray);
    return flattenArray;
};


function deleteFunctions(arr){
    for (var k in arr) {
        var element = arr[k];
        if (isFunction(element)) {
            var index = arr.indexOf(element);
            if (index > -1) {
                arr.splice(index, 1);
            }
        }
    }
}

function isFunction(functionToCheck) {
    var getType = {};
    return functionToCheck && getType.toString.call(functionToCheck) === '[object Function]';
}

var array = [1, 2, [3, 4], [5, 6]];
console.log(array.flatten());
console.log(array);

var array1 = [1, 2, 3, 4];
console.log(array1.flatten());
console.log(array1);

var array2 = [0, ["string", "values"], 5.5, [[1, 2, true], [3, 4, false]], 10];
console.log(array2.flatten());
console.log(array2);

Related

1. flatten()

   Array.prototype.flatten = function () {
       return this.reduce((p,c) => p.concat(c), [])
   

2. flatten()

   Array.prototype.flatten = function () {
       function flattenArrayOfArrays(array, result) {
           if (!result) {
               result = [];
           for (var i = 0; i < array.length; i++) {
               if (Array.isArray(array[i])) {
                   flattenArrayOfArrays(array[i], result);
               } else {
   ...
   

3. flatten()

   Array.prototype.flatten = function() {
     return this.reduce(function(res, el) {
       if(el.constructor == Array) {
         el.forEach(function(sub_el) {
           res.push(sub_el);
         })
       } else {
         res.push(el);
       return res;
     }, []);
   

4. flatten()

   Array.prototype.flatten = function () {
     var toReturn = [];
     for (var i = 0, len = this.length; i < len; i++) {
       if (this[i] instanceof Array) {
         toReturn = toReturn.concat(this[i].flatten());
       } else {
         toReturn.push(this[i]);
     return toReturn;
   };
   

5. flatten()

   Array.prototype.flatten = function() {
     return this.reduce(function(a,b) {
       return a.concat(b)
     }, [])
   

6. flatten()

   var slice = Array.prototype.slice;
   Array.prototype.flatten = function () {
     var obj, result = [];
     for (var i = 0, l = this.length; i < l; ++i ) {
       obj = this[ i ];
       if ( Array.isArray( obj ) ) {
         result = result.concat( obj.flatten() );
       } else {
         result[ result.length ] = obj;
   ...
   

7. flatten()

   Array.prototype.flatten = Array.prototype.flatten || function() {
     'use strict';
     var that = this;
     for (var i = 0; i < that.length; i += 1) {
       if (Array.isArray(that[i])) {
         that = that.concat.apply([], that);
         i -= 1;
     return that;
   };
   Array.prototype.flatten1 = Array.prototype.flatten1 || function() {
     'use strict';
     var res = [];
     (function flatten(arr) {
       for (var i = 0; i < arr.length; i += 1) {
         if (Array.isArray(arr[i])) {
           flatten(arr[i]);
         } else {
           res.push(arr[i]);
     }(this));
     return res;
   };
   Array.prototype.flatten2 = Array.prototype.flatten2 || function() {
     'use strict';
     for (var i = 0; i < this.length; i += 1) {
       if (Array.isArray(this[i])) {
         this.splice.apply(this, [i, 1].concat(this[i].flatten()));
     return this;
   };
   var a = [1, 2, [3, 4, [5, 6]]];
   console.log(a.flatten()); 
   console.log(a); 
   console.log(a.flatten1()); 
   console.log(a); 
   console.log(a.flatten2()); 
   console.log(a); 
   

8. flatten()

   var arrays = [[1, 2, 3], [4, 5], [6]];
   console.log(arrays.reduce(function(a, b){
     return a.concat(b);
   }));
   Array.prototype.flatten = function(){
     return this.reduce(function(a, b){
       if(!Array.prototype.isPrototypeOf(a))
         a = [a];
       else
   ...
   

9. flatten(array)

   Array.prototype.flatten = function(array) {
     return this.reduce((prev, next) => prev.concat(next), []);
   };