Array Flatten is JS

gistfile1.txt

function flatten(array) {
    var result = [];
    var nodes = array || array.slice();
    var node;

    if (!array.length) {
        return result;
    }

    node = nodes.pop();

    do {
        if (Array.isArray(node)) {
            nodes.push.apply(nodes, node);
        } else {
            result.push(node);
        }
    } while (nodes.length && (node = nodes.pop()) !== undefined);

    result.reverse(); // we reverse result to restore the original order
    return result;
}