If you want both horizontal and vertical scrollbars, you have to say: -scollbars es, not -scrollbars e -scrollbars s

Those named parameters are indeed hash elements, to reassign them, simply overwrites the existing value.

One example:

use Tk;
use strict;
use warnings;

sub something {
    my $box = shift;
    $box->delete("1.0", "end");
    $box->insert("end", $_) for (1 .. 100);
}

my $mw = MainWindow->new(title=>"Scrollbar Demo");
my $box = $mw->Scrolled(qw/Text -width 100 -height 15 -scrollbars se/)
+->pack;
$mw->Button(text=>"click", command=>[\&something, $box])->pack;
MainLoop;
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