Dear monks,

I'm trying to adapt the OO example of the Inline::C cookbook. I'd like to have setters that return $self. Some stuff sort of seems to be working, but returning $self isn't:

use strict;
use warnings;

my $parent = Node->new('Parent');
my $child  = Node->new('Child');

# this DWIM... (prints 'Parent')
print $child->set_parent($parent)->get_parent->get_name, "\n";

# ...but $child is now undef, (Can't call method ... )
$child->set_name('New name');
print $child->get_name, "\n";

#################################
package Node;

use Inline C => q{

    typedef struct {
        char* name;
        double branch_length;
        struct Node* parent;
        struct Node* previous_sister;
        struct Node* next_sister;
        struct Node* first_daughter;
        struct Node* last_daughter;
    } Node;
    
    
    SV* new(char* class, char* name) {
        Node* node   = malloc(sizeof(Node));
        SV* obj_ref  = newSViv(0);
        SV* obj      = newSVrv(obj_ref, class);
        node->name   = strdup(name);        
        sv_setiv(obj, (IV)node);
        SvREADONLY_on(obj);        
        return obj_ref;
    }
    
    SV* set_name(SV* self, char* name) {
        ((Node*)SvIV(SvRV(self)))->name = strdup(name);
        return self;
    }
    
    char* get_name(SV* self) {
        return ((Node*)SvIV(SvRV(self)))->name;
    }
    
    SV* set_parent(SV* self, SV* parent) {
        ((Node*)SvIV(SvRV(self)))->parent = parent;
        return self;
    }
    
    SV* get_parent(SV* self) {
        return ((Node*)SvIV(SvRV(self)))->parent;
    }
    
    void DESTROY(SV* self) {
        Node* node = (Node*)SvIV(SvRV(self));
        free(node->name);
        free(node);
    }

};
[download]

...And I get:

% perl inline.pl
Parent
Can't call method "get_name" on an undefined value at inline.pl line 1
+0.
[download]

So what is the correct way to return self so it doesn't turn into undef?

(P.s.: I am user rvosa, but I'm away from my computer, forgot my password and lost the email address the reminder was sent to.)

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