Hi Monks, I must be missing something but can't see what it is. I'm creating what is essentially a singleton class. These are the two commands I am running on the singleton class. 
Encoder::Config::set_config_file($config_file);
my $config_obj = Encoder::Config::get_instance;

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The code (incomplete) it is calling is below. 
package Encoder::Config;

my $global_config_file;
my $called;
my $instance = undef;

sub get_instance { 
    my $default_config_file = '../etc/system.ini'; 
    return $instance if defined $instance;
        $instance = {};
    bless $instance;
    if ($global_config_file) {
       $instance->load_config($global_config_file);    
    } else {
       $instance->load_config($default_config_file);
    }           
    return $instance;
}


sub set_config_file {
    $global_config_file = shift;
    return if $called;
    $called = 1;
}

[download]
What's odd is that defined $instance in the get_instance sub always returns true. I went through the debugger, and sure enough, as soon as I enter get_instance my global $instance variable seems to be a hash. Any feedback is greatly appreciated

In reply to Global and autovivification? by kalium

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