Exception Handler

The exception handler is a default or custom function, which is called once an exception has exhausted all available try-catch blocks.

The execution stops once the handler has been called : as such, it is possible to log or display information related to debugging.

The exception handler is different from the try/catch block : the latter allows the execution to carry on, when the exception is processed.

<?php
function exception_handler(Throwable $exception) {
  echo "Uncaught exception: " , $exception->getMessage(), "\n";
}

set_exception_handler('exception_handler');

throw new Exception('Uncaught Exception');
echo "Not Executed\n";
?>

Documentation

Related : Try-catch