Hello,

I just learned another lesson about variable scope, names and packages, but I am not sure which of my solutions should be prefered.

I have a quite great number (about 40) of slightly different objects, so I created a base class and used a macro to generate the code for the specialized subclasses with their differing attribute, which is a constant list of values (simplified, untested code):

package Baseclass;
# common attributes and methods
sub use_values {
   croak ("Abstract class");
}

package Subclass_1;
use base 'Baseclass';
my @values = (...);
sub use_values { ... }

package Subclass_2;
use base 'Baseclass';
my @values = (...);
sub use_values { ... }

[download]

This did not work, as the package statement does not affect the scope of @values.

One solution would be to name them different (e.g. @Subclass_1_values), which would keep me typing the rest of the day and does not increase readability.

One solution would be to wrap it in a function: 

package Subclass_1;
use base 'Baseclass';
sub use_values {
   my @values = (...);
   ...
}

[download]
Does that initialize the list everytime the method is called? Not very efficient then.

Next try is a local scope: 

package Subclass_1;
use base 'Baseclass';
{
  my @values = (...);
  sub use_values { ... }
}

[download]

Should work, but I do not like the increased indenting.

What else can I try? What are your experiences?

Thank You for comments.

And it came to pass that in time the Great God Om spake unto Brutha, the Chosen One: "Psst!"
(Terry Pratchett, Small Gods)

In reply to Multiple Package in one file with equal named variables by Brutha

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