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# reset_event_handler(+EventId)

Resets the handler for the event EventId to its default value

EventId
  Atom or Integer.

## Description

If EventId is an error number, the error handler is reset to its default value, cancelling any previous redefinition.

If EventId is an atom, any previously installed handler is uninstalled, and future occurrences of the event will cause an error (32).

### Modes and Determinism

- reset_event_handler(+) is det

### Exceptions

(4) instantiation fault
  EventId is not instantiated.
(5) type error
  EventId is neither atom nor integer.
(6) out of range
  EventId is integer, but not a valid error number.

## Examples

    Success:
        ?- event(hello).
        warning: no handler for event in hello
        yes.

        ?- set_event_handler(hello, writeln/1).
        yes.

        ?- event(hello).
        hello

        ?- reset_event_handler(hello).
        yes.

        ?- event(hello).
        warning: no handler for event in hello
        yes.

## See Also

current_error / 1, get_event_handler / 3, error / 2, error / 3, event / 1, set_event_handler / 2