anchor.diff:          $('body').prepend(
             section {id: 'todoapp'}, [
               header {id: 'header'}, [
  -              h1 {}, ['todos']
  +              h1 'todos'
                 input {
                   id: 'new-todo'
                   type: 'text'
                   placeholder: 'What needs to be done?'
                   autofocus: true
  -                init: -> @keydown (e) =>
  +                keydown: (e) ->
                     if e.which == 13
                       tasks.push(new Task(@val().trim()))
                       @val('')
  
positive.code:                     # <http://stackoverflow.com/questions/12325066/button-click-event-fires-when-pressing-enter-key-in-different-input-no-forms>
                }
              ]
              div {}, bind ->
                if tasks.length() == 0
                  []
                else
  
negative.code:                             class: 'edit'
                              autofocus: true
                              value: task.title.get()
                              keyup: (e) ->
                                if e.which == 13
                                  @blur()
                              blur: ->
                                task.title.set(@val())
                                task.isEditing.set(false)
                            }
                          ] else [
                            input {
                              class: 'toggle'
                              type: 'checkbox'
                              checked: bind -> task.isCompleted.get()
                              change: -> task.isCompleted.set(@is(':checked'))
                            }
                            label {
                              dblclick: ->
                                task.isEditing.set(true)
                                editBox.focus()
                            }, bind -> "#{task.title.get()}"
                            button {
                              class: 'destroy'
                              click: -> tasks.remove(task)
                            }
                          ]
                    ]
                    footer {id: 'footer'}, [
                      span {id: 'todo-count'}, bind -> [
                        strong "#{incomplete()}"
                        if incomplete() == 1 then ' item left' else ' items left'
                      ]
                      button {
                        id: 'clear-completed'
                        click: ->
                          tasks.replace(task for task in tasks.all() when not task.isCompleted.get())
                      }, 'Clear completed'
                    ]
                  ]
            ]
  