     else
       # In this branch we receive an Event name and props object.
       # The props object may also include options for the emission, such as
-      # { layer }, { target } or { base }.
+      # { layer }, { target }, { base } or { log }.
       # up.emit([target], eventName, [eventPropsAndEmitOptions])
       options.event = up.event.build(args[0], u.except(options, 'target'))
 

      'target',
      'event',
      'base',
      'callback'
      # 'boundary'
    ]


  logEmission: ->
    return unless up.log.isEnabled()

    message = @log

    if u.isArray(message)
      [message, messageArgs...] = message
