Hello monks

This is a basic question regarding calling subrutines with \& ... but I have problems in finding an answer. Given the Perl Tk code below (basically a file "dropper") I want to pass to the subrutine one more variable, in my example the dummy $SomeVariable. How can I achive it? And: where does the $selection in the subrutine comes from (it was not explicitally passed to it)? Thanks in advance to illuminate me.

#!/usr/local/bin/perl -w

use Tk;
use Tk::DropSite;
use strict;
use vars qw($top $drop);

$top = new MainWindow;
$top->Label(-text => "The drop area:")->pack;
$drop = $top->Scrolled('Listbox',
               -scrollbars => "osoe",
              )->pack;
my $SomeVariable="xxx";
$drop->DropSite
  (-dropcommand => [\&accept_drop, $drop],
   -droptypes => ($^O eq 'MSWin32' ? 'Win32' : ['KDE', 'XDND', 'Sun'])
  );
MainLoop;

sub accept_drop {
    my($widget, $selection) = @_;

    my $filename;
    eval {
    if ($^O eq 'MSWin32') {
        $filename = $widget->SelectionGet(-selection => $selection,
                          'STRING');
    } else {
        $filename = $widget->SelectionGet(-selection => $selection,
                          'FILE_NAME');
    }
    };
    if (defined $filename) {
    $widget->insert(0, $filename);
    }
}

__END__

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In reply to Calling subrutine with \& and passing variables by IB2017

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