Nodejs Array Where where(exp)

Method Source Code

Array.prototype.where = function(exp){
    var exp = new Function("$", "return " + exp);
    var arr=[];/*from  w  w w  .  j ava 2 s  .  co  m*/
    for(var i=0; i<=this.length-1; i++){
        if(exp(this[i])){
            arr.push(this[i])
        }
    }
    return arr;
};

Array.prototype.collect = function(exp){
    var exp = new Function("$", "return " + exp);
    var arr=[];
    for(var i=0; i<=this.length-1; i++){
        arr.push(exp(this[i]))
    }
    return arr;
};
Array.prototype.join = function(arr){
    this.joined_data = arr;
    return this;
};

Array.prototype.as = function(key,exp){
    var exp = new Function("$",key, "return " + exp);
    var arr=[];
    
    for(var i=0; i<=this.length-1; i++){
        for(var j=0; j<=this.joined_data.length-1; j++){
            if(exp(this[i], this.joined_data[j])){
                var obj = {};
                for(var k in this[i]) {
                    if((this[i]).hasOwnProperty(k)) {
                        obj[k] = this[i][k]
                    }
                }
                obj[key] = this.joined_data[j];
                arr.push(obj)
                //this[i][key]=this.joined_data[j];
            }
        }
    }
    return arr;
};

Related

1. where(_cond)

   Array.prototype.where = function (_cond) {
       var items = []; 
       for (var l = 0; l < this.length; l++) {
           if (_cond(this[l])) {
               items.push(this[l]);
       return items;
   };
   ...
   

2. where(argument)

   Array.prototype.where = function(argument) {
     return this.filter(item => argument(item));  
   };
   

3. where(attribut, value)

   Array.prototype.where = function (attribut, value) {
       var res = [];
       for (var i = 0; i < this.length; i++) {
           if (this[i][attribut] == value)
               res.push(this.slice(i, i + 1));
       return res;
   };
   

4. where(callback)

   Array.prototype.where = function(callback){
     if(!callback) return;
     for(var i = 0; i < this.length; i++){
       if(callback(this[i])){
         return this[i];
   

5. where(f)

   Array.prototype.where = function(f){
      var fn = f;
      if(typeof f == 'string'){
         if((fn=lambda(fn)) == null){
            throw "Syntax error in lambda string: "+ f;
   };
   

6. where(f)

   Array.prototype.where = function(f){
       var newArray = [];
       for(var i = 0; i < this.length; i++){
           if(f(this[i])){
               newArray.push(this[i]);
       return newArray;
   };
   ...
   

7. where(func)

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

8. where(func)

   Array.prototype.where = function(func){
     var result = [];
     forEach(this, function (element) {
       if(func(element)){
         result.push(element);
     });
     return result;