I recently found and started to use App::Config and have been suitably impressed by its power and flexibility in integrating command line and configuration file parameters. There was one little urksome feature I found however - the requirement to define configuration parameters one line at a time. eg.

my $cfg = App::Config->new({
    'CASE'  =>  0
});

$cfg->define("effective_group", { 
    'DEFAULT'   =>  "nogroup" 
});
$cfg->define("effective_user", { 
    'DEFAULT'   =>  "nobody" 
});
$cfg->define("http_port", { 
    'DEFAULT'   =>  "localhost:8080", 
    'CMDARG'    =>  [ "-p" ], 
    'ARGCOUNT'  =>  1 
});
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I ideally wanted a different model of behaviour which would allow me to pass all configuration definitions in a single hash for both clarity and ease of maintainability. The result was the small 'local' module which I wrote below - It is certainly not worthy of CPAN or alike, but others may find it useful. The methods define, get, load (equivalent of cfg_file from App::Config) and set are included in this module.

The configuration definition code snippet from above can be rewritten as thus:

my $cfg = Local::Config->new({
    'CASE'  =>  0
}, {
    'effective_group'   =>  {
        'DEFAULT'   =>  "nogroup" 
    },
    'effective_user'    =>  {
        'DEFAULT'   =>  "nobody" 
    },
    'http_port'         =>  {
        'DEFAULT'       =>  "localhost:8080",
        'CMDARG'        =>  [ "-p" ],
        'ARGCOUNT'      =>  1
    }
});
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package Local::Config;

use strict;
use vars qw/$VERSION @ISA @EXPORT @EXPORT_OK/;

require Exporter;
require AutoLoader;

@ISA = qw/Exporter AutoLoader/;
@EXPORT_OK = qw//;

$VERSION = '0.24';

use App::Config;

sub define {
    my $self = shift;
    return undef unless defined $self->{config};
    my $arg = @_;
    if (ref($arg) eq 'HASH') {
        $self->{config}->define($_, ${$arg}{$_}) foreach keys %{$arg};
    };
    return;
};

sub get {
    my $self = shift;
    return $self->{config}->get(@_);
};

sub load ($) {
    my $self = shift;
    return undef unless -e $_[0];
    return $self->{config}->cfg_file($_[0]);
};

sub new {
    my $param = shift;
    my $class = ref($param) || $param;
    my $self = {};
    bless ($self, $class);
    my $args = (ref($_[0]) eq 'HASH') ? $_[0] : {};
    $self->{config} = App::Config->new(\%{$args});
    if (ref($_[1]) eq 'HASH') {
        $self->{config}->define($_, ${$_[1]}{$_}) foreach keys %{$_[1]
+};
    };
    return $self;
};

sub set {
    my $self = shift;
    return $self->{config}->set(@_);
};

1;

__END__
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