threads::shared hash

[fxmakers]

Hi!

Here's my code:

use threads;
use threads::shared;

my %hash : shared;
my $var = "hello";

$hash{'foo'}{'bar'} = 1; 
$hash{$var}{'bar'} = 1;

Script is not interpreted and returns: Invalid value for shared scalar at test.pl line 7.
Can't create a shared hash of hashes.
$hash{'foo'} = 1; #works fine.
perl -v: This is perl, v5.8.2 built for cygwin-thread-multi-64int

Any ideas?
Thanks!

-UPDATED POST-

Edited by Chady -- added code tags.

[BrowserUk]

Seems to be a problem with your build of perl rather than perl itself, in that I don't get any errors (other than the missing semicolons) running your snippet under 5.8.2/AS 808

This is perl, v5.8.2 built for MSWin32-x86-multi-thread
Binary build 808 provided by ActiveState Corp. http://www.ActiveState.
+com

That said, your snippet obviously isn't a direct c&p of your failing code (given the syntax errors), and the partial error message you give "Invalid value for shared scalar at..." is usually a compile or runtime error, not a crash. So maybe you should post a more complete example?

P:\test>perl -Mthreads -mthreads::shared
my( %h ) : shared;
my $var = 'hello';
$h{ $var } = 123;
print $h{hello};
^Z
123

[fxmakers]

You're right, I did some mistakes, I just modified my post :P
A shared hash works fine, but
the creation of a shared hash of hashes is the problem:

use threads;
use threads::shared;
use strict;

my %hash : shared;
my $var = "hello";

$hash{'foo'}{'bleh'} = "test";
$hash{$var}{'foo'} = "test";

Both 'foo' or $var keys returns the error: Invalid value for shared scalar.

[BrowserUk]

Unfortunately, autovivification doesn't auto-share, so you have to manually create shared elements.

#! perl -slw
use strict;
use threads;
use threads::shared;
use Data::Dumper;

my %hash : shared;
my $var = 'hello';

$hash{ foo } = &share( {} );
$hash{ foo }{ bleh } = 'test';

$hash{ $var } = &share( {} );
$hash{ $var }{ foo } = 'test';

print Dumper \%hash;
__END__
P:\test>test
$VAR1 = {
          'foo' => {
                     'bleh' => 'test'
                   },
          'hello' => {
                       'foo' => 'test'
                     }
        };

Note: The &shared( {} ); syntax is required. See threads::shared for details.

[tilly]

Random advice.

Unless you can give a really good reason why you should, you probably don't want to use Perl's thread implementation. If you think that you have a good reason, I'd still not recommend pushing it very far.

[liz]

Ack.

Random link. ;-)

Liz