Figure out the structure of an object to arbitrary depth in mongo (or anything else running V8)

structure.js

function structure(anObject, maxDepth) {
    if (maxDepth < 1) {
        return Array.isArray(anObject)
            ? []
            : typeof(anObject) === "object"
                ? {}
                : typeof(anObject);
    }

    var clone; 

    if (typeof(anObject) === "object") {
        clone = Array.isArray(anObject) ? [] : {};
        for (var key in anObject) {
            clone[key] = structure(anObject[key], maxDepth-1);
        }
    } else {
        clone = typeof(anObject);
    }

    return clone;
}