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Future::Exception

NAME

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

SYNOPSIS

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";
}
}

DESCRIPTION

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.

CONSTRUCTOR

from_future
$e = Future::Exception->from_future( $f )

Constructs a new "Future::Exception" wrapping the given failed future.

ACCESSORS

$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.

METHODS

throw
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.

as_future
$f = $e->as_future

Returns a new "Future" object in a failed state matching the exception.

AUTHOR

Paul Evans <leonerd AT leonerd DOT org DOT uk>

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