Nodejs Array Where where(argument)

Method Source Code

// Make the following works

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

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(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;
   };
   

3. 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];
   

4. where(exp)

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

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;
   };