Yes this looks like the right teack however I tried to modify it to do what I wanted but get an error when I try to split $_ 
use Tk;
use strict;
use warnings;

my $mw = new MainWindow(title => "demo");
my $entry = $mw->Scrolled("Text", -scrollbars => 'e', -font => '12')->
+pack(-side => 'bottom', 
                     -fill => 'both', -expand => 1);
#$entry->bind("<KeyRelease>", [sub {print $_[1];}, Ev('A')]);
$entry->bind("<KeyRelease>", [\&color, Ev('A')]);

$entry->tagConfigure("blue", -foreground => "blue");

MainLoop;

sub color {
   my $count = 0;
   my @char = split(//, $_);
   my @word = split(/ /, $_);

   foreach my $char (@char) {
      $count++;
   }

   foreach my $word (@word) {
      if ($word =~ /color/) {
         my $len = length($word);
         my $from = "1\.$count";
         my $next = $from + $len;
         $entry->tagAdd("blue", $from, $next);
      }
   }
}

[download]
The error says that $_ is not initialized but $_1 is? Why is this so and how can I accomplish what I want to do in this sub if I cannot use $_?

In reply to Re: Re: Tk Scrolled textbox, parse on input? by Elijah
in thread Tk Scrolled textbox, parse on input? by Elijah

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