completeError method Null safety

void completeError (
  1. Object error,
  2. [StackTrace? stackTrace]

Complete future with an error.

Calling complete or completeError must be done at most once.

Completing a future with an error indicates that an exception was thrown while trying to produce a value.

If error is a Future, the future itself is used as the error value. If you want to complete with the result of the future, you can use:


or if you only want to handle an error from the future:



void completeError(Object error, [StackTrace? stackTrace]);