If whitespace or start/end of string is going to be the delimiter, I would use: 

c:\@Work\Perl\monks>perl -wMstrict -le
"my $title = 'C .NET Cobol .NET .NET .NETER Perl C++ C+ xC++ C+++ C++x
+ xC x.NET .net';
 ;;
 for my $kw (qw(.NET C C++)) {
   my $count = () = $title =~ m{ (?<! \S) \Q$kw\E (?! \S) }xmsig;
   print qq{'$kw' $count};
   }
"
'.NET' 4
'C' 1
'C++' 1

[download]

Give a man a fish:  <%-{-{-{-<

In reply to Re^3: Regex help \b & \Q by AnomalousMonk
in thread Regex help \b & \Q 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.