.each() JavaScript implementation

each.js

function each (collection, callback) {
    var x, len;
    if(Utils.isArray(collection)) {
        x = -1;
        len = collection.length;
        while(++x < len) {
            if (callback(x, collection[x]) === false) {
                break;
            }
        }
    } else if(Utils.isPlainObject(collection)) {
        for(x in collection) {
            if(collection.hasOwnProperty(x)) {
                if (callback(x, collection[x]) === false) {
                    break;
                }
            }
        }
    }
}