This is not a suggestion for the jQuery core; it’s just something I required recently that some of you may find useful/intriguing…

jQuery.fn.map = (function(_map) {
 
    return function(toMap, prop, jQueryOb) {
 
        if (typeof toMap === 'string') {
 
            var parts = toMap.match(/(\:|[^:])+/g),
                method = parts.shift(),
                args = parts,
                mapped = _map.call(this, function(){
                    var $this = $(this),
                        result = $this[method].apply( $this, args );
                    return prop ? result[prop] : result;
                });
 
            return jQueryOb ? mapped : mapped.get();
 
        } else {
            return _map.apply(this, arguments);
        }
 
    };
 
})(jQuery.fn.map);
 
// Note: this only modifies $.fn.map; not $.map

It allows you to pass a string to $(collection).map(...) instead of a function; it’s useful for returning attributes, DOM properties, CSS styles or data tied to each element without having to spend time/space writing a function, e.g.

$('a').map('attr:href'); // => ['http://abc.com', 'http://123.com', ... (all HREFs)
$('p').map('css:fontSize'); // => ['16px', '12px', '19px' ... (all font-sizes)
$('.class').map('offset', 'left'); // => ['200px', '430px', ... (all left offsets)
$('div').map('data:someData'); // => ['data', ... (added via jQuery.fn.data)

The first argument is split at each colon (use to escape a colon), the first part of the split string is assumed to be the jQuery method name which you want to call (e.g. "css" => $().css()). All remaining parts are assumed to be arguments for that method. The second argument (to map()) is an optional property to access following retrieval; this is demonstrated with the “offset” example in the code above. The last argument is a boolean; passing true will make it return a jQuery object instead of a real array.

Thanks for reading! Please share your thoughts with me on Twitter. Have a great day!