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RegisterUnaryCallbackHandler typedef
The type of a custom Zone.registerUnaryCallback implementation function.
Receives the Zone that the handler was registered on as self, a delegate forwarding to the handlers of self's parent zone as parent, and the current zone where the error was uncaught as zone, which will have self as a parent zone.
The function f is the function which was passed to the which was passed to the Zone.registerUnaryCallback of zone.
The handler should return either the function f or another function replacing f, typically by wrapping f in a function which does something extra before and after invoking f
The function must only access zone-related functionality through self, parent or zone. It should not depend on the current zone (Zone.current).
Implementation
typedef RegisterUnaryCallbackHandler = ZoneUnaryCallback<R, T> Function<R, T>(
Zone self, ZoneDelegate parent, Zone zone, R Function(T arg) f);
© 2012 the Dart project authors
Licensed under the BSD 3-Clause "New" or "Revised" License.
https://api.dart.dev/stable/2.18.5/dart-async/RegisterUnaryCallbackHandler.html