Beefy Boxes and Bandwidth Generously Provided by pair Networks
Welcome to the Monastery

Comment on

( #3333=superdoc: print w/ replies, xml ) Need Help??

As others wrote already there is no way to make this work. The important thing to remember is that prototypes are NOT subroutine signatures! Prototypes do not exist to allow you to specify the number and type of arguments! They exist to allow you to create (very occasionally) a subroutine that works as a builtin. Take push() for example. If you pass (@arr, 1,2,3) to an ordinary subroutine, then the subroutine receives a list containing all elements in @arr followed by 1, 2 and 3 and has no way to modify the @arr array. push() on the other hand receives the array and then the 1, 2 and 3 and can modify the array.

If for whatever reason you feel the need to create a subroutine that is used the same as push(), you can use a prototype to tell Perl to change the way its parameters are handled, but you should not attempt to use it to validate that a subroutine gets the expected number of parameters!

The only prototype an ordinary programmer should ever use is the empty one for constant subroutines (and even then  use constant ... is better) and MAYBE ($) for subroutines that are to be used in mathematical expressions. All other prototypes are best left to a few module authors.

Enoch was right!
Enjoy the last years of Rome.

In reply to Re: effects of ampersand and non ampersand when referencing a sub name by Jenda
in thread effects of ampersand and non ampersand when referencing a sub name by ISAI student

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, 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, 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.
  • Log In?

    What's my password?
    Create A New User
    and the web crawler heard nothing...

    How do I use this? | Other CB clients
    Other Users?
    Others rifling through the Monastery: (6)
    As of 2015-12-02 06:25 GMT
    Find Nodes?
      Voting Booth?

      My keyboard shows this many letters:

      Results (35 votes), past polls