If you want to use a regular expression, I believe that you're going to have to consume the original string, ala: 
use strict;
use warnings;
my $count;
# get $input from some place
$input =~ s/^\s+//; # dump leading whitespace
while ($input =~ s/[^\s]+\s+//)
{
  ++$count;
}
++$count if ($input =~ /./); # catch the last word

[download]
but, I think, what you really want is 'split': 
my @array = split /\s+/, $input;
$count = scalar (@array);

[download]
--
Wade

In reply to Re: Counting in regular expressions by wade
in thread Counting in regular expressions 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.