#!/usr/bin/perl
use warnings;
no warnings 'redefine';
use strict;
#right click for menus
use Tk;
use Tk::TextEdit;
use Tk::TextUndo;

my $top = new MainWindow;
my $textedit = $top->TextEdit->pack;
$textedit->SetGUICallbacks([sub {}]);
MainLoop;


sub Tk::TextUndo::insertStringAtStartOfSelectedLines{
   my ($w,$insert_string)=@_;
   $w->addGlobStart;
   my @sel_lines = $w->SelectedLineNumbers;
   $w->MarkSelectionsSavePositions;
     foreach my $line (@sel_lines){
        $w->insert($line.'.0', $insert_string);
     }
$w->RestoreSelectionsMarkedSaved;
$w->addGlobEnd;
}


sub Tk::TextUndo::deleteStringAtStartOfSelectedLines{
   my ($w,$insert_string)=@_;
   $w->addGlobStart;
   my @sel_lines = $w->SelectedLineNumbers;
   $w->MarkSelectionsSavePositions;
   my $length = length($insert_string);
     foreach my $line (@sel_lines){
        my $start = $line.'.0';
        my $end   = $line.'.'.$length;
        my $current_text = $w->get($start, $end);
        next unless ($current_text eq $insert_string);
        $w->delete($start, $end);
     }
$w->RestoreSelectionsMarkedSaved;
$w->addGlobEnd;
}
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