Sample of some CoffeeScript from AndBug's Navi utility

navi.coffee

layout_local = (k, v) ->
    $('<div class="local">k = v</div>').text("#{k} = #{v}")

layout_frame = (f) ->
    div = $('<div class="frame"></div>')
    div.append($('<h3></h3>').text("Frame: " + f[0]))
    div.addClass('native') if f[2]
    div.append(layout_local l[0], l[1]) for l in f[2..]
    div.hide()
    return div

layout_thread = (t) ->
    div = $('<div class="thread"></div>')
    div.append($('<h3></h3>').text("Thread: " + t[0]))
    div.append(layout_frame f) for f in t[1..]
    return div

$ -> 
    threads = eval($('#forest').text())    
    $('#content').append(layout_thread t) for t in threads
    $('#content').children().first().find('.frame').show()
    $('.thread > h3').click (evt) -> 
        $('.frame').hide()
        console.log(this.parent)
        $(this).parent().find('.frame').show()