deleteSetting: (setting) ->

    log('deleteSetting ' + setting.value)

    key = @keyForSetting.get(setting.value)

    row = @settings.get(key)

    if row? and not row.setting.equals(setting)

      throw new Error('corrupt row for ' + setting.value)

    row.onChangeFunc(null) if row?.onChangeFunc?

    @settings.delete(key)

    @keyForSetting.delete(setting)

  clear: ->

    new Map(@settings).forEach (row, key) ->

    @settings.clear()

    @keyForSetting.clear()

  forAll: (cb) ->

    all = Array.from(@keyForSetting.keys())

    for s in all

      cb(@graph.Uri(s))

  allSettingsStr: ->

    @keyForSetting.keys()

class GraphToControls