The most obvious difference to me is the presence of a colon, which seems to be what you've used in your own logic. How about instead of returning true if it contains no colon, you try returning false if it contains one? 
foreach (@data) {
  my $match = $_ if !/:/;
}

[download]
The issue you are having is that you need the entire string to contain no colons, but what you have tested for is actually that it contains non-colon characters. The closest code to your spec would be 
foreach (@data) {
  my $match = $_ if /^[^:]*$/;
}

[download]
which says that all characters between the start and end of the string are not colons.

Advanced use case, this is exactly the sort of thing grep was made for: 

my ($match) = grep !/:/, @data;

[download]

Update: Fixed typo in case two; thanks AnomalousMonk.

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: Help with a small regex by kennethk
in thread Help with a small regex by cspctec

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.