JavaScript to use prevAll like jQuery?

Question

How to achieve this in JavaScript?

function prevAll (element) {
    // some code to take all siblings before element?
    return elements;
};

Answer 1

With .previousElementSibling, you get the previous node that's an actual element (not a text node or comment).

function prevAll(element) {
    var result = [];

    while (element = element.previousElementSibling)
        result.push(element);
    return result;
}

The .previousElementSibling property can be polyfilled in IE8 if needed.

I should note that IIRC, jQuery returns the elements in document order. If that's the case and if that's what you need, just .reverse() the array when you return it.