NAME

Thread::Queue::Any - thread-safe queues for any data-structure

SYNOPSIS

    use Thread::Queue::Any;
    my $q = Thread::Queue::Any->new;
    $q->enqueue("foo", ["bar"], {"zoo"});
    my ($foo,$bar,$zoo) = $q->dequeue;
    my ($foo,$bar,$zoo) = $q->dequeue_nb;
    my $left = $q->pending;

DESCRIPTION

A queue, as implemented by Thread::Queue::Any is a thread-safe data structure that inherits from Thread::Queue. But unlike the standard Thread::Queue, you can pass (a reference to) any data structure to the queue.

Apart from the fact that the parameters to enqueue are considered to be a set that needs to be enqueued together and that dequeue returns all of the parameters that were enqueued together, this module is a drop-in replacement for Thread::Queue in every other aspect.

Any number of threads can safely add elements to the end of the list, or remove elements from the head of the list. (Queues don't permit adding or removing elements from the middle of the list).

FUNCTIONS AND METHODS

new

The new function creates a new empty queue.

enqueue LIST

The enqueue method adds a reference to all the specified parameters on to the end of the queue. The queue will grow as needed.

dequeue

The dequeue method removes a reference from the head of the queue, dereferences it and returns the resulting values. If the queue is currently empty, dequeue will block the thread until another thread enqueues.

dequeue_nb

The dequeue_nb method, like the dequeue method, removes a scalar from the head of the queue and returns it. Unlike dequeue, though, dequeue_nb won't block if the queue is empty, instead returning undef.

pending

The pending method returns the number of items still in the queue.

CAVEATS

Passing unshared values between threads is accomplished by serializing the specified values using Storable when enqueuing and de-serializing the queued value on dequeuing. This allows for great flexibility at the expense of more CPU usage. It also limits what can be passed, as e.g. code references can not be serialized and therefor not be passed.

AUTHOR

Elizabeth Mattijsen, <liz@dijkmat.nl>.

Please report bugs to <perlbugs@dijkmat.nl>.

COPYRIGHT

Copyright (c) 2002 Elizabeth Mattijsen <liz@dijkmat.nl>. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

SEE ALSO

threads, threads::shared, Thread::Queue.