Everyone is so much quicker than me. Oh well, here's my attempt for what it's worth, constructed to handle some (by no means all) HTML-legal variations in the text.

#!/usr/bin/perl -w
use strict;

$/  = '';

my %h;

while (<DATA>){
  while ( s/((\d+) is good.+?)<(?:hr|HR)>//s ){
    my $good  = $1;
    my $key   = $2;
    $good     =~ s/\n?\s?<(?:BR|br).?.?>\n?/|/g;
    my @pot   = split /\|/, $good;
    shift @pot;
    $h{$key}  = [@pot];
  }

}

use Data::Dumper;
print Data::Dumper->Dump([\%h],[qw(*h)]);

__DATA__
<HR>
1 is good<BR>
useless data<BR>useless data<BR>
useless data
<BR>useless data<BR>
<hr>
2 is good<BR>
useless data<br>
useless data<BR>
useless data<br>
useless data<BR>
<hr>
3 is not good <BR>
useless data
  <br />useless data<br />useless data<BR>
useless data<BR>
<HR>
4 is good<BR>
useless data<BR>useless data<BR>
useless data<br>useless data<BR>
<HR>
5 is not good <BR>
useless data<BR>
useless data<BR>
useless data<BR>
useless data<BR>
<HR>

[download]

By the way, you asked your question very well and complete with a good data example. It's appreciated.
(better Data::Dumper, thanks to sacked and tilly).
mkmcconn

In reply to Re: parsing with regex by mkmcconn
in thread parsing with regex by 2501

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.