Future::Exception
- an exception type for failed Futures
use Scalar::Util qw( blessed );
use Syntax::Keyword::Try;
try {
my $f = ...;
my @result = $f->result;
...
}
catch {
if( blessed($@) and $@->isa( "Future::Exception" ) {
print STDERR "The ", $@->category, " failed: ", $@->message, "\n";
}
}
The get
method on a failed Future instance will throw an exception to indicate that the future failed. A failed future can contain a failure category name and other details as well as the failure message, so in this case the exception will be an instance of Future::Exception
to make these values accessible.
Users should not depend on exact class name matches, but instead rely on inheritence, as a later version of this implementation might dynamically create subclasses whose names are derived from the Future failure category string, to assist with type matching. Note the use of ->isa
in the SYNOPSIS example.
$e = Future::Exception->from_future( $f );
Constructs a new Future::Exception
wrapping the given failed future.
$message = $e->message;
$category = $e->category;
@details = $e->details;
Additionally, the object will stringify to return the message value, for the common use-case of printing, regexp testing, or other behaviours.
Future::Exception->throw( $message, $category, @details );
Since version 0.41.
Constructs a new exception object and throws it using die()
. This method will not return, as it raises the exception directly.
If $message
does not end in a linefeed then the calling file and line number are appended to it, in the same way die()
does.
$f = $e->as_future;
Returns a new Future
object in a failed state matching the exception.
Paul Evans <leonerd@leonerd.org.uk>