functional.js

// Double all numbers
> Promise.map([1, 2, 3], function(num) { return num * 2; }).then(function(numbers) { console.log("The final list of numbers:", numbers); })
The final list of numbers: [ 2, 4, 6 ]

// Remove all the odd numbers
> Promise.filter([1, 2, 3], function(num) { return (num % 2) == 0; }).then(function(numbers) { console.log("The final list of numbers:", numbers); })
The final list of numbers: [ 2 ]

// Sum all the numbers
> Promise.reduce([1, 2, 3], function(total, num) { return total + num; }, 0).then(function(number) { console.log("The final value:", number); })
The final value: 6