Dear Monks,
as a newbie in Perl I use snippets of the others' code and try to understand them.
Now I have a piece of code which works but I do not understand why.
I pass arguments to a subroutine as follows (I need a populated hash in the subroutine): 
sub marine($string, \%hash)

[download]

Then I take the parameter in the subroutine:
sub marine
{
my $line = shift;
my(%hash) = %{(shift)};
...
}

[download]
The line that I do not understand is my(%hash) = %{(shift)};. Why there are parenthesis there? Could you please explain this?
Thank you!

In reply to hash to sub by Anonymous Monk

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