I am trying to use, in the base class, a class constant defined in a derived class. e.g.

in file Thingy.pm 

package Thingy;

sub new {
   my ($class, $line) = @_;
   my $thingy = {}; 
   ...
   if ($line =~ m/$PATTERN/) {
      ...
   }
   bless $thingy, $class;
}
1;

[download]

in file Rubber.pm 

package Rubber;
@ISA = qw(Thingy);
use vars $PATTERN = q(...);
1;

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and later in the main script 

use Rubber;
my $line = ...;
my $thing = Rubber->new($line);

[download]

but I always get 'use of unitialised value in regex compilation...'

Trying $class::PATTERN doesn't work either.

What am I doing wrong - how do I reference the constant in derived classs Rubber from the method in base class Thingy?

In reply to class constants in derived classes by leriksen

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