Did you create MainWindow object.
I have executed your code like the following.

use strict;
use warnings;

use Tk;
my $mainWindow=MainWindow->new;
my $textEntry = $mainWindow->Entry(-state => 'normal') -> pack( -side 
+=> 'bottom', -expand => 'BOOLEAN');
$textEntry -> bind('<Return>' => &get);
sub get {
    my $text = $textEntry -> get();
    print "$text\n";
}
MainLoop;

[download]
It worked correctly for me.

In reply to Re: Tk Error by kiruthika.bkite
in thread Tk Error by k0rn

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