in reply to scalars, references and queues

Sharing a reference to something that isn't shared is an error. As threads::share says, 

my $var :shared;
$var = 1;              # ok
$var = [];             # error
$var = &share([]);     # ok

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Maybe Thread::Queue should handle references better. Fortunately, it's easy to fix. Just share the referenced hash. 

my %hash :shared = ( ... );
$DataQueue->enqueue(\%hash);

[download]

or 

# Fixed as per BrowserUK's reply.
# Initialization must be done after share.
my $href = share({});
%$href = ( ... );
$DataQueue->enqueue($href);

[download]

or 

use Storable qw( freeze thaw );
my %hash = ( ... );
$DataQueue->enqueue(freeze(\%hash));

[download]

Untested.

Update: Added Storeable snippet. Rephrased some text.

Replies are listed 'Best First'.
Re^2: scalars, references and queues
by BrowserUk (Patriarch) on Aug 03, 2007 at 15:38 UTC

    A note of caution. Using 

    my $href = { ... };
$DataQueue->enqueue(share($href));

    [download]

    Is dangerous, because whatever you put inside the anonymous hash, represented in your exampe by ..., will be silently discarded when you do share( $href ).

    You must share the reference first, and then populate it.

    Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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