is an option for asynchronous operations that specifies functions to apply when events are generated.


  • The typical setting for HandlerFunctions is "event1"->f1,"event2"->f2,, which specifies that when eventi is generated, the function fi should be applied to an association whose elements are specified by HandlerFunctionsKeys.
  • The events that can be generated by particular tasks are listed under the functions that submit the tasks.
  • In the HandlerFunctions association, the special element "UnhandledEvent"->f uses the function f for any event for which no explicit handler was specified.


Basic Examples  (8)

Display the result of evaluation after the task is finished:

Print the complete Association available to a handler function:

Display the result of Print evaluated in a subkernel:

Display a dialog when a message is generated:

Print messages generated by the subkernel:

Handle the "BodyReceived" event when it is generated by URLSubmit:

Store the headers with a variable when they are received:

Print the status code and content type when the task is finished:

Introduced in 2016