You are right

#!/usr/bin/perl -w
use strict;
use Tk;

my $main = Tk::MainWindow->new;

my $test = $main->Listbox()->place(-in => $main, -x => 10, -y => 10);
print "Test is $test\n";

MainLoop;

__END__
Test is Tk::Listbox=HASH(0x83c9684)
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