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I haven't written perl in a while, so I've forgotten how to tell perl that 0 is valid to initialize a value.

The warning Use of uninitialized value is bugging me a lot. I don't like having any warnings.

I have a list of characters who have appeared in one or more books. There is one character whose first book notation is the number 0. The split on line 10 is said to be uninitialized. On line 12, $first_book in the $first_type is also uninitialized. On line 13, the removal of the non-digit characters in the $first_book, also says $first_book is an uninitialized value. That value is in fact initialized. Because the first book can contain alphabetical characters, I can't simply add a +0 to it.

Any suggestions on how to tell perl that 0 initializes the string?

I did not come up with this notation system, but I can't think of anything to replace it that won't make the data too long. I feel silly asking this, but I can't think of anything right now. Also, if you know who Bink is or recognize the titles of the novels and want to ask me what I am doing; please use PMs. Thanks! 8)

use strict;
use warnings;

my @novel_list = map { chomp $_; $_ } <DATA>;

my $Bink_books = 'M1, M2, m3, m4, 6, m7, M9, m11, m13, 14, 17, m19, m2
+1, M22, m23, m31, 35, 36, m37, m40, m41';
my $Quan_books = '0';

for my $books ($Bink_books, $Quan_books) {
  my @novels = split(/, /, $books); # $books is initialized for Quan e
+ven though the value is 0.
  my $first_book = $novels[0];
  my $first_type = $first_book =~ /^M/ ? 'major' : $first_book =~ /^m/
+ ? 'mentioned' : undef;
     $first_book =~ s/\D//g;
  my $first_novel = $novel_list[$first_book]; # was my $first_novel = 
+$novel_list->[$first_book];

  print "$first_novel is the first novel the character was in.\n";
}

__DATA__
Other source
A Spell for Chameleon
The Source of Magic
Castle Roogna
Centaur Aisle
Ogre, Ogre
Night Mare
Dragon on a Pedestal
Crewel Lye: A Caustic Yarn
Golem in the Gears
Vale of the Vole
Heaven Cent
Man from Mundania
Isle of View
Question Quest
The Color of Her
Demons Don't Dream
Harpy Thyme
Geis of the Gargoyle
Roc and a Hard Place
Yon Ill Wind
Faun and Games
Zombie Lover
Xone of Contention
The Dastard
Swell Foop
Up in a Heaval
Cube Route
Currant Events
Pet Peeve
Stork Naked
Air Apparent
Two to the Fifth
Jumper Cable
Knot Gneiss
Well-Tempered Clavicle
Luck of the Draw
Esrever Doom
Board Stiff
Five Portraits
Isis Orb
Ghost Writer in the Sky
[download]

No matter how hysterical I get, my problems are not time sensitive. So, relax, have a cookie, and a very nice day!

Lady Aleena

In reply to How to get 0 to initialize a value by Lady_Aleena

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