Bless, inheritance and swig

From: Xiaodong Huang (xhuang_at_yahoo.com)
Date: 03/31/04 

Date: 30 Mar 2004 16:17:13 -0800

I searched but could not find answer for this question on Internet or
in Newsgroups.

I have a class CObject in C++ which is wrapped by SWIG:

class CObject {
public:
  CObject();
  get();
}

I want to write a perl object that inherits from
CObject. So I wrote something like this (I used similar code
before in non-SWIG case):

Package MyPerlObject;

use Exporter;
use CObject;

our @ISA = qw(CObject Exporter);

sub new {
    my $class = shift ;
    $class = ref($class) || $class ;
    my $self = CObject->new();
    bless $self, $class;
    return $self;
}

...

MyPerlObject does not have a method get(). When client of MyPerlObject
called MyPerlObject::get() at run-time, I got
"No matching function for overloaded CObject_get()".

So I tried to pinpoint where the problem was and found that it seemed
to have something to do with bless.

I modified the above new() subroutine by adding two lines:

sub new {
    my $class = shift ;
    $class = ref($class) || $class ;
    my $self = CObject->new();
    $self->get(); # works
    bless $self, $class;
    $self->get(); # does not work
    return $self;
}

The line before "bless" statement works but the line after it gives me
the "No matching function .." error as before.

Could someone point to me what I did wrong or suggest a way to work around
the problem?

Thanks.

xh