To elaborate on LanX’s comments:

Before using Perl prototypes you should study Tom Christiansen’s essay, “Far More than Everything You’ve Ever Wanted to Know about Prototypes in Perl, ” which is available within the Monastery here. To quote from the opening:

Nearly any programmer you encounter will, when asked what function prototypes are for, report the standard text-book answer that function prototypes are mainly used to catch usage errors at compile time in functions called with an unexpected type or number of parameters. This is what programmers are expecting of prototypes, and what Perl does not give them.

Think coercion rather than checking, and you’ll be closer to the mark. Read the article, then use prototypes only for those specialised cases where they’re really useful.

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re^3: Automatic vivification of an object by Athanasius
in thread Automatic vivification of an object by bounsy

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.