Beefy Boxes and Bandwidth Generously Provided by pair Networks
Don't ask to ask, just ask
 
PerlMonks  

Comment on

( #3333=superdoc: print w/ replies, xml ) Need Help??
If you need particular types in your parameters, another way to achieve this (and quite possibly more robust than prototype as the clinical dissection above shows) is to use the "program by contract" paradigm.

So if you need the first parameter to be an array ref, put in code to test this precondition -

sub PUSH { my ($aref, @new) = @_; carp "first parameter must be an array reference" unless ref $aref e +q 'ARRAY'; ... }

Even better, use Params::Validate

If your emulating a builtin like push, using the same interface has advantages (in this case positional parameters), but I prefer using named parameters as much as possible - it also can cut out a number of errors if you choose appropriate parameter names e.g.

sub NAMED_PUSH { my(%args) = @_; carp "dest_aref parmeter must be an array reference" unless ref $arg +s{dest_aref} eq 'ARRAY'; ... }

Your POD for this sub (dont give me that puzzled look !!!) should document what keys are expected, and the code checks you have keep your part of the contract.

use brain;


In reply to Re^2: Gratuitous use of Perl Prototypes by leriksen
in thread Gratuitous use of Perl Prototypes by grantm

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!
  • 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
  • Outside of code tags, you may need to use entities for some characters:
            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?
    Username:
    Password:

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

    How do I use this? | Other CB clients
    Other Users?
    Others lurking in the Monastery: (13)
    As of 2014-10-21 11:15 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?

      For retirement, I am banking on:










      Results (100 votes), past polls