Hrmm....this is what I get: 
line 7:
(15) "detsen nested"

line 8:
(0) "i prefer pi"
(2) "prefer pi ip referp"
(9) "pi ip"

[download]
That seems to be correct. Nothing else shows up in line 7, because "testest" isn't a palindrome (but "testseet" is).

I guess it's helpful if you indicate what you think the output should be, so I can short circuit this back and forth :)

Changing line 7 to this: 

nested testset detsen nested

[download]
I get this: 
line 7:
(0) "nested testset detsen"
(7) "testset"
(15) "detsen nested"

[download]
What did you expect on the 2 lines you added?

-QM
--
Quantum Mechanics: The dreams stuff is made of

In reply to Re^7: regex at word boundary by QM
in thread regex at word boundary by mikeraz

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.