sub SUBNAME($@;\%) This subroutine above is called with a scalar, array and followed by an optional hash...

Others, more worthy than I, have dealt with the hashref parameter. The @ does not mean an array, it means a list. Consider:
sub mysub($@\%) {
    my ($one, @two, $ref) = @_;
    print "@two\n";
}

mysub('a','b','c','d');

[download]
Gives:
b c d

[download]
The minimum length of a list is zero elements, so the following "works" (in that no error is reported) as well:
mysub('a');

[download]
If you want to force an array, use \@. Prototypes are useful for forcing the correct type of reference being passed at compile-time (as opposed to runtime checks) but are so easy to circumvent, even accidently, that they can lull you into a false sense of security.

In reply to Re^2: What's the better Perl style? Define parameters or not? by cdarke
in thread What's the better Perl style? Define parameters or not? by pureHeart

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.