CGI.pm does something simliar, except with a generic sub. 
sub self_or_default {
    return @_ if defined($_[0]) && (!ref($_[0])) &&($_[0] eq 'CGI');
    unless (defined($_[0]) &&
        (ref($_[0]) eq 'CGI' || UNIVERSAL::isa($_[0],'CGI')) # slightl
+y optimized for common case 
        ) {
    $Q = $CGI::DefaultClass->new unless defined($Q);
    unshift(@_,$Q);
    }
    return wantarray ? @_ : $Q;
}

[download]
Then they use it like this: 
sub url_param {
    my ($self,@p) = self_or_default(@_);
    my $name = shift(@p);
    return undef unless exists($ENV{QUERY_STRING});
...

[download]

In reply to Re: Answer: How do I make object methods callable as non-OO functions? by cazz
in thread How do I make object methods callable as non-OO functions? by trammell

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.