Make Javascript do List Comprehension

Question

What is the cleanest way to make Javascript do something like Python\'s list comprehension?

In Python if I have a list of objects whose name\'s I want to \'

Answer 1

A list comprehension has a few parts to it.

1. Selecting a set of something
2. From a set of Something
3. Filtered by Something

In JavaScript, as of ES5 (so I think that's supported in IE9+, Chrome and FF) you can use the map and filter functions on an array.

You can do this with map and filter:

var list = [1,2,3,4,5].filter(function(x){ return x < 4; })
               .map(function(x) { return 'foo ' + x; });

console.log(list); //["foo 1", "foo 2", "foo 3"]

That's about as good as it's going to get without setting up additional methods or using another framework.

As for the specific question...

With jQuery:

$('input').map(function(i, x) { return x.name; });

Without jQuery:

var inputs = [].slice.call(document.getElementsByTagName('input'), 0),
    names = inputs.map(function(x) { return x.name; });

[].slice.call() is just to convert the NodeList to an Array.