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function preloadImages(arr) {
    var newimages = [],
        loadedimages = 0;
    var postaction = function() {};
    arr = (typeof arr != "object") ? [arr] : arr;

    function imageloadpost() {
        loadedimages++;
        if (arr[loadedimages - 1] === null) {
            log('nothing here');
        }
        if (loadedimages == arr.length) {
            postaction(newimages);
            for (var j = 0, len = arr.length; j < len; j++) {
                $(arr[j]).append(newimages[j]);
                $(arr[j]).removeAttr("data-src");
            }

        }
    }

    var img;
    for (var i = 0, len = arr.length; i < len; i++) {
        img = new Image();
        newimages.push(img);

        img.addEventListener("load", function() {
            imageloadpost();
        });
        img.addEventListener("error", function() {
            imageloadpost();
        });
        if (arr[i].getAttribute('data-src') !== null) {
            img.src = arr[i].getAttribute('data-src');
            img.alt = "";
        }
    }
    return {
        done: function(f) {
            postaction = f || postaction;
        }
    };
}