Beefy Boxes and Bandwidth Generously Provided by pair Networks
more useful options
 
PerlMonks  

comment on

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

You can't do it the way you're trying, because during the creation of the object "$obj" your code is referring to "$obj" itself which doesn't exist yet! That's kind of like trying to define a word by using the same word in its definition:

"A recursive algorithm is an algorithm which recursively calls itself +to produce an answer"

You have a couple of choices. The first is to use the second snippet of code you showed (which you already know works, since it waits until the object $obj is fully defined before trying to reference its data).

Or you could construct the object without referencing the object itself:

use strict; use warnings; package MakeObject; use Data::Dumper; my $rootDir = '/home'; my $userId = 'smith'; my $appName = 'project'; my $obj = MakeObject->new; printf "Object contents => %s\n", Dumper($obj); sub new { my $obj = bless { Root => $rootDir, UserDir => "$rootDir/Usr/$userId/", UserAppData => "$rootDir/Usr/$userId/$appName/", }, shift; return $obj; } __END__ Output is: Object contents => $VAR1 = bless( { 'Root' => '/home', 'UserDir' => '/home/Usr/smith/', 'UserAppData' => '/home/Usr/smith/project/' }, 'MakeObject' );

Since the latter has the same effect -- it only refers to data which is already defined ($rootDir, $userId and $appName, but not $obj) -- it doesn't create the catch 22 effect of the original code.

say  substr+lc crypt(qw $i3 SI$),4,5

In reply to Re: reference to an undefined key by golux
in thread reference to an undefined key by exilepanda

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, 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?
    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 rifling through the Monastery: (3)
    As of 2020-03-29 21:41 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?
      To "Disagree to disagree" means to:









      Results (171 votes). Check out past polls.

      Notices?