Hello monks I am curious about a little question to do with how PERL deals with compilation of modules. I'm not sure specifically how to state the question as I have only just begun to perceive that the question exists. Lets say you have a module; 

package Model::Conf;

use Exporter;
use base 'Exporter'; 

our @EXPORT = qw( $conf );

our $conf = { 'somevar' => 'somevalue' };

$conf->{'foo'} = bar();


sub bar() { return 'bar'; }

1;

[download]
does the subroutine "bar" run every time I put use Model::Conf in other packages? If so, and assuming I want the code only to run once at compile time and its result to be accessible in any other package I put use Model::Conf in, would the following be correct; 
package Model::Conf;

use Exporter;
use base 'Exporter'; 

our @EXPORT = qw( $conf );

our $conf = { 'somevar' => 'somevalue' };

$conf->{'foo'} = bar() unless $conf->{'foo'};

sub bar() { return 'bar'; }

1;

[download]
The reason I ask is that I want to be able to put use Model::Conf in various other packages without the sub "bar" being run each time and wasting OPCODES on a very tight little MVC 'micro'-framework I am working on for the educational benefit, and I am not sure if the above is the right way to be going or what. Any thoughts? Many thanks.

In reply to package compiling by simonodell

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