use strict;
use warnings;
use Tk;

sub subbie_1 {
    my ($widget, $txt, $entry_var) = @_;

    $txt->insert('end', "$$entry_var\n");
}


# Main Window
my $mw = new MainWindow;
my $entry_var = 'Some text';

#GUI Building Area
my $frm_name = $mw -> Frame()->pack();
my $lab = $frm_name -> Label(-text=>"Name:")->pack(-side=>'left');
my $ent = $frm_name -> Entry(-textvariable=>\$entry_var)->pack();

#Text Area
my $textarea = $mw -> Frame()->pack();
my $txt = $textarea -> Text(-width=>40, -height=>10)->pack();

$ent->bind('<Return>' => [\&subbie_1, $txt, \$entry_var]);

MainLoop();

##</code><code>##

...

sub subbie_1 {
    my ($widget, $txt) = @_;

    $txt->insert('end', $widget->get () . "\n");
}


...

$ent->bind('<Return>' => [\&subbie_1, $txt]);

MainLoop();