Your problem is the .*? -- although you rightly tried to limit the number of don't care characters using '?' your match still grabs the smallest number of don't care characters between '<!--' and 'DOS'... which just happens to include another '-->' and '<!--', the pieces it isn't supposed to grab.

You'll need a few baselines to come up with a workable regexp:

These would help you optimize your regexp...

But the key point is that you need to limit your regexp to a single comment group containing 'DOS'.

I'd suggest using:

$html = '<!--% xxxx UNO xxxx %-->   <!--% xxxx DOS xxxx %-->';
$html =~ s/<!--%([^->]+?) DOS ([^->]+)%-->/GONE/s;
print $html;

[download]

It's a little ugly, and notice that it assumes that your 'xxxx' can't contain '->', which may or may not be the case.

YMMV

In reply to Re: UNO DOS by jreades
in thread UNO DOS, HTML by Anonymous Monk

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.