Underscore Extension Methods FilterMap

Allow to filter and map a collection in a single loop for better performance.

Usage

Introduction

var myArray = [
    { productId: 1, title: 'My Product 1', price: 10, quantity: 1 },
    { productId: 2, title: 'My Product 2', price: 15.5, quantity: 4 },
    { productId: 3, title: 'My Product 3', price: 7.25, quantity: 1 }
];

Simple usage

var titles = _.filterMap(myArray, function(obj) { 
    if (obj.price >= 10)
        return obj.title; 
});
// titles === ['My Product 1', 'My Product 2']