If i understand you correctly, it's the "Factory method" pattern case. I'm using it for storage abstraction. 

package Storage::Factory; {
    use Storage::SQLite;
    use Storage::MySQL;

    sub new {
        my $class = shift;
        my $opt = {@_};

        return Storage::SQLite->new(file => $opt->{dsn}) if $opt->{typ
+e} eq 'sqlite';
        return Storage::MySQL->new(dsn => $opt->{dsn}) if $opt->{type}
+ eq 'mysql';
    }
}
1;


use Storage::Factory;

my $storage = Storage::Factory->new(%{ $self->plugin('Config')->{db} }
+)

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In reply to Re: Can a class constructor create an instance of a derived class and return it? Or, can objects transmute into other objects? by alexander_lunev
in thread Can a class constructor create an instance of a derived class and return it? Or, can objects transmute into other objects? by poodad

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