Hello QuillMeantTen,

Thanks for drawing attention to the Doomsday algorithm, it looks interesting.

Given that your code was written as a learning exercise, I will highlight one aspect that stands out as a problem: the use of subroutine prototypes.

First, Perl prototypes don’t function as a programmer coming from C or Java might expect them to, and they’re mostly unneeded anyway. This is explained at length in Tom Christiansen’s article “Far More Than Everything You’ve Ever Wanted to Know about Prototypes in Perl,” which is reprinted as a PerlMonks tutorial here.

But, second, none of the subroutine prototypes in your code is ever actually used — because the & sigil prepended to a subroutine call disables them! See perlsub#Prototypes. Unless you have a good reason to disable prototypes, you should call a subroutine like this:

frobnicate();

[download]

and not like this:

&frobnicate;

[download]

The latter form is seen mainly in legacy code dating from Perl’s earlier days.

Update: Fixed typo.

Hope that helps,

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

In reply to Re^2: Doomsday algorithm (prototypes) by Athanasius
in thread Doomsday algorithm by QuillMeantTen

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.