I'm trying to create a singleton wrapper around the Perl DBI class, but getting problems.

I think I'm missing something to specify the correct class.

Here is the code i'm using:

package Singleton::DBI; 

use conf::SiteConfig;
use DBI qw/ :sql_types / ;      # Database interface

use vars qw( @ISA);
@ISA = qw(DBI);
  
my $oneTrueSelf;
  
sub instance 
{
    $oneTrueSelf ||= (shift)->new();
}
  
sub new 
{
    my $type = shift;

    # get necessary config info
    my $dbuser = conf::SiteConfig::get_conf ( 'dbuser' );
    my $dbpass = conf::SiteConfig::get_conf ( 'dbpass' );
    my $dbname = conf::SiteConfig::get_conf ( 'dbname' );
    my $dbserv = conf::SiteConfig::get_conf ( 'dbserv' );
    
    # Build up DBI connection string.
    my $datasource = 'dbi:mysql:'.$dbname;
    $datasource .= "\;host=$dbserv" if ( $dbserv );

    # Connect
    my $this  = DBI->connect ( $datasource, $dbuser, $dbpass );
    return bless $this, $type;
}


1;

[download]

The error I see is:

Can't locate auto/Singleton/DBI/selectrow_a.al  ...

[download]

I suspect that I'm not modify the ISA type properly, so that the returned instance of Singleton::DBI is not treated identically as a DBI object, but I'm a little unclear on how inheritance works in Perl.

In reply to Problem creating a singleton wrapper around DBI by Anonymous Monk

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