Update: after reading Re: What is the fastest way to download a bunch of web pages? i've reworked this function to follow the same pattern. Notice that Thread::Queue only takes scalars, so if you want to push funky data through the queue, one way is to freeze/thaw it. 
use strict;
use warnings;
use Data::Dumper;
use threads;
use Thread::Queue;
use Storable qw(freeze thaw);
 
my $slow_matches_b = sub { sleep 1;
                           return unless $_[0];
                           return 1 if $_[0] =~ /b/;
                         };
my $test_strings = [ ('blee','blah','bloo', 'qoo', 'fwee' ) ];

my @results = threaded_map( 2, $slow_matches_b, @$test_strings );

print Dumper \@results;


sub threaded_map
{
    my $thread_count = shift;
    my $function = shift;

    #
    #    setup work queues
    #
    my $id = 0;
    my $input_q = new Thread::Queue;
    my $result_q = new Thread::Queue;
    for (map { [ $id++, $_ ] } @_)
    {
        $input_q->enqueue(freeze($_));
    }
    
    #
    #    define worker function to run in each thread
    #
    my $worker_function = sub 
    {
        while ( my $frozen_work = $input_q->dequeue_nb )
        {
            my $work = thaw($frozen_work);
            my $id = $work->[0];
            my $input_data = $work->[1];
            my $result = $function->($input_data);
            my $frozen_result = freeze( [ $id, $result ] );
            $result_q->enqueue($frozen_result);
        }
    };

    #
    #    create workers that will read from shared input queue and wri
+te to shared output queue
    #
    my @threads = map{ threads->create( $worker_function ) } 1 .. $thr
+ead_count;
    $_->join for @threads;

    #
    #    join the results data together
    #
    my %results;
    while ( my $frozen_result = $result_q->dequeue_nb )
    {
        my $result = thaw($frozen_result);
        $results{$result->[0]} = $result->[1];
    }

    #
    #    return results in order received
    #
    return map { $results{$_} } sort keys %results;
}

[download]

In reply to threaded map by LanceDeeply
in thread Using functional programming to reduce the pain of parallel-execution programming (with threads, forks, or name your poison) by tphyahoo

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