Provided by: libfuture-perl_0.41-1_all bug


       "Future::Exception" - an exception type for failed Futures


          use Scalar::Util qw( blessed );
          use Syntax::Keyword::Try;

          try {
             my $f = ...;
             my @result = $f->get;
          catch {
             if( blessed($@) 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 <>