docs: function () { $assertEveryCalledOnce (function (method, before, after) {
  
          var compo = $singleton (Component, {
                          method: $bindable (function (x) { method ()
                              return 42 }) })
  
          compo.method.onBefore (function (_5) { before ()
              $assert (this === compo)
              $assert (_5, 5) })
  
          compo.method.onAfter (function (_5, _result) { after ()
              $assert (this === compo)
              $assert (_5, 5)
              $assert (_result, 42) })
  
          $assert (compo.method (5), 42) }) }