creating class base modules

Avox has asked for the wisdom of the Perl Monks concerning the following question:

I'm relatively new to perl. Wrote some scripts but would like to make them into a class/module. I'm having trouble, however. I've come up with a very simple example that I'm having trouble getting to work. So if a wise monk could tell me what I'm doing wrong, I'd be grateful. I'm using ActivePerl 5.6.1 on NT.

-----test.pl-------
use Cat;

$mycat = cat->new();
$mycat->feed("fish");
exit;


-----Cat.pm-------
package Cat;

use strict;
use warnings;
our $VERSION = '0.01';
our @ISA = ();


sub new
{
    my $class = shift;
    my $self = { Stomach => "empty" }; 
    bless $self, $class;
    return $self;
}
sub feed
{
   my ( $self, $food ) = @_;
   $self->{ Stomach } = $food if defined $food;
   return $food;
}

1;
__END__
[download]

When I run test.pl, I get this error: Can't locate object method "new" via package "cat" (perhaps you forgot to load "cat"?) at test.pl line 3. I hope I'm just doing something stupid. Thanks all!

Comment on creating class base modules Download Code

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Re: creating class base modules by Fletch (Bishop) on Dec 17, 2002 at 15:47 UTC
Read The Fine Error. `'cat' ne 'Cat'`. Case matters.	[reply] [d/l]
Re: creating class base modules by adrianh (Chancellor) on Dec 17, 2002 at 15:48 UTC
`cat->new` should be `Cat->new`. Package names are case sensitive :-)	[reply] [d/l] [select]
Re^2: creating class base modules by Aristotle (Chancellor) on Dec 17, 2002 at 16:00 UTC
And for that matter, just about everything else is in Perl, too. Makeshifts last the longest.	[reply]
Re: creating class base modules by stephen (Priest) on Dec 17, 2002 at 15:49 UTC
Capital C for Cat. Classes are case sensitive in Perl. So your code should read: `$mycat = Cat->new();` [download] stephen	[reply] [d/l]
Re: creating class base modules by Avox (Sexton) on Dec 17, 2002 at 15:57 UTC
DOH! Thanks guys/gals. /me slaps head a couple times for good measure. Thats what I needed folks. heh...	[reply]
Re: creating class base modules by aging acolyte (Pilgrim) on Dec 17, 2002 at 16:17 UTC
On a similarly simple question regarding using classes. What are the advantages/disadvantages in using `export= qw( &new &feed )` [download] or export_ok Do things need to be exported? thanks A.A. Update Sorry I realise that this is a bit off topic and should have appeared as an seperate question	[reply] [d/l]
Re: Re: creating class base modules by pfaut (Priest) on Dec 17, 2002 at 16:27 UTC
`export` forces the listed symbols into the callers namespace. `export_ok` allows the listed symbols to be pulled into the callers namespace. `export_ok` is nicer as it gives the user of your module the choice. See Exporter for details. Exports pollute the namespace of the module user. If you must export try to use @EXPORT_OK in preference to @EXPORT and avoid short or common symbol names to reduce the risk of name clashes. `--- print map { my ($m)=1<<hex($_)&11?' ':''; $m.=substr('AHJPacehklnorstu',hex($_),1) } split //,'2fde0abe76c36c914586c';` [download]	[reply] [d/l] [select]