docs: function () {
          var compo = $singleton (Component, {
                          somthingHappened: $triggerOnce () })
  
          $assertEveryCalled (function (first, second) {
              compo.somthingHappened (function (what) { $assert (what, 'somthin'); first () })
              compo.somthingHappened (function (what) { $assert (what, 'somthin'); second () })
              compo.somthingHappened ('somthin') }) }