Re: trying to subclass DBI

The connect() method needs to be in a MySubDBI::dr package (that's dr not db)

Tim.

On Thu, Dec 29, 2005 at 12:39:39AM +0100, wernerus sebastien wrote:
> Hi,
>
> I'm new to OO programming, and i'd like to subclass DBI for some purpose.
>
> I made some tests to figure out how it worked. Here is a sample code
> that doesn't do anything interesting. It doesn't execute as I
> expected:
>
> ======================
> package MySubDBI;
>
> use strict;
>
> use DBI;
> use vars qw(@ISA);
> @ISA = qw(DBI);
>
> package MySubDBI::db;
> use vars qw(@ISA);
> @ISA = qw(DBI::db);
>
> sub connect {
> my ($drh, @args) = @_;
> my $dbh = $drh->SUPER::connect(@args) or return;
> $dbh->{private_mysubdbi_test} = 'blabla';
> print "test0\n";
> return $dbh;
> }
>
> sub test {
> my $dbh = shift;
> return $dbh->{private_mysubdbi_test};
> }
>
> package MySubDBI::st;
> use vars qw(@ISA);
> @ISA = qw(DBI::st);
>
> package Main;
>
> my $dbn = "DBI:mysql:database=***:host=***:port=***";
>
> my $dbh = MySubDBI->connect( $dbn, '***', '***' );
> if ( $dbh ) { print "connection ok\n" } else { print "connection error\n" }
>
> print 'test1: ', $dbh->{private_mysubdbi_test}, "\n";
> print 'test2: ', $dbh->test, "\n";
> ======================
>
> It prints:
> connection ok
> test1:
> test2:
>
> Do you know why it doesn't print the string 'test0' and nothing for
> test1 and test2 ?
.

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