Dear fellow monks.

In a recent project I used an abstract base class as an interface and implemented its abstract methods using constants (for the sake of clarity; please see my code below).

Reading the docs for 'constants' I can't see anything wrong with this usage (constants become inline functions at compile time and I can override functions).

Now a colleague claims that I cannot rely on this behaviour because constants become *inline* functions and so the lookup might crash in some (unknown?) cases.

Well, the code works. But since it is supposed to run on a customers system and I don't want to have to fix it later if we run into trouble, I've decided to approach a higher instance:
so esteemed monks let me please ask you: is this approach okay or do you see any problems?
Or better: is this implementation considered harmful?

Thanks in advance!
k

Father.pm

package Father;
use warnings;
use strict;

sub new {
  my $class = shift;
  my $self  = {};
  bless ($self, $class);
  return $self;
}


# INTERFACE
sub aText {
  #implement
  die('Parent aText');
}

sub aList {
  # implement
  die('Parent aList');
}
1;
[download]

Son.pm

package Son;
use warnings;
use strict;

use Father;
use base qw(Father);

use constant {
  aText => 'This is a Text',
  aList => [qw(aaa bbb ccc)],
};

sub print_son {
  my $self = shift;  
  print 'Son:', $self->aText(), "\n";
  print 'Son: ', join(', ', @{$self->aList()}), "\n";
}

1;
[download]

test.pl

#! /usr/bin/perl
use strict;
use warnings;


use Son;

my $s = Son->new();
print $s->aText(), "\n";
print join(', ', @{$s->aList()}), "\n";

$s->print_son();
[download]

Output:

This is a Text
aaa, bbb, ccc
Son:This is a Text
Son: aaa, bbb, ccc