Dear Monks, I'm just trying to put together a small prototype for some fun and learning on text mining/parsing but I've come a cropper on regexing a larger block that I normally do (usually simple finding tasks or look ahead/look behind). I've got a series of texts where the only common point is Sidenote: <blah> at the beginning of each text which I want to use as the splitting point so that I can turn the whole file into a series of xml objects (in due course) to use later.
When I print out I get
but I had thought that a pattern match as above would give me everything starting with [Sidenote: in one div then start a new div for the next [Sidenote: but clearly there is something that I have misunderstood in the tutorials. 
use strict;
use warnings;

my $text = "C:\\letters.txt";

my @letters;
open(IN, $text) || die "Can't open $text";
@letters = <IN>;
close(IN);
chomp @letters;

foreach my $indiv_note (@letters) {
  my $letter_text = ($indiv_note =~ /(^\[Sidenote (?: (?!^\[Sidenote).
+ )* )/);
  print "<div>$letter_text</div>\n";
}

[download]
The sort of data that I using is: 
[Sidenote: The same.]

                                                     _Sunday Evening._

       *       *       *       *       *

I have at this moment got Pickwick and his friends on the Rochester
coach, and they are going on swimmingly, in company with a very
different character from any I have yet described, who I flatter mysel
+f

[Sidenote: Miss Hogarth.]

                            FURNIVAL'S INN, _Wednesday Evening, 1835._

MY DEAREST KATE,

The House is up; but I am very sorry to say that I must stay at home. 
+I
have had a visit from the publishers this morning, and the story canno
+t

[download]

In reply to Regexing a block of text in between patterns by Anonymous Monk

Title:
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