calculateDOMDepth.coffee

calculateDOMDepth = (doc = document)->
    max = 0
    _calculateDOMDepth = (dom)->
        domdepth = dom.dataset.domdepth = parseInt(dom.parentNode.dataset.domdepth) + 1
        max = domdepth if domdepth > max
        Array.prototype.forEach.call dom.children, (child)->
             _calculateDOMDepth(child)
    body = doc.body
    body.parentNode.dataset.domdepth = 0
    _calculateDOMDepth(body)
    max
    
console.log calculateDOMDepth(document)
console.log calculateDOMDepth()