use threads;
use threads::shared;

my %h : shared;
$h{test} = [];

Invalid value for shared scalar at (eval 4) line 1, <> line 4.

my $ar = [];

$h{test} = $ar;
Invalid value for shared scalar at (eval 6) line 1, <> line 6.

share $ar;

$h{test} = $ar;

## No error this time. 

##</code><code>##

use threads;
use threads::shared;

my %h : shared;
my $ar : shared = [];
$h{test} = $ar;

##</code><code>##

use threads;
use threads::shared;
my %h : shared;
my $ar = [];
$h{test} = share( $ar );

##</code><code>##

use threads;
use threads::shared;
my %h : shared;
$h{test} = share( [] );
Type of arg 1 to threads::shared::share must be one of [$@%] (not single ref constructor) at (eval 6) line 1, near "] )"