use strict;
use warnings;
use Tk;

my $mw = MainWindow->new;
my $entry = $mw->Entry();
my $label = $mw->Label(-justify=>'left');
my $but1 = $mw->Button(-text=>"go",-command=>\&go);

$but1->place(-x=>10,-y=>10,-width=>50,-height=>20);
$entry->place(-x=>10,-y=>40,-width=>50,-height=>20);
$label->place(-x=>10,-y=>70,-width=>50,-height=>20);

MainLoop;

sub go{
	my $text = $entry->get;
	$label->configure(-text=>$text)};