I want to create generic objects if the package does not already exists. This is to keep me from creating a bunch of nearly identical modules that all do the same thing. The only thing that really changes is the package name. So I wrote this code, which I thought would work but I am not so sure.

#################################################
sub _create_new_package_for {
    my $self    = shift;
    my $package = _get_package_name( shift );
    
    eval "use $package"; ## no critic
    return $package if not $EVAL_ERROR;

    my $eval_package =<<"END";
package ${package};

use strict;
use warnings;
use English qw( -no_match_vars );

use base 'Generic::Tree';
use base 'Generic::Container';
1;
END
    eval $eval_package; ## no critic
    croak $EVAL_ERROR if $EVAL_ERROR;

    return $package;
}

[download]

The issue I see here is that the new 'package' does not seemed to be stored. So I can use it once, but if I want to 'use' a generic package that has already been created, it will not allow itself to be identified with a 'use' statement. So it will always eval the package code again. To me that did not seem correct. Example:

$self->_create_new_package_for( 'Testing::Package' );
$self->_create_new_package_for( 'Testing::Package' );

[download]

From the above code, I would assume, that the first time I initialize this namespace. So the second time I execute the subroutine it would be 'usable'. It is not, so what is it that I am missing and how can I fix it?

In reply to Dynamically create Packages by Herkum

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