Hi, Monks

How do I properly extend a class?

I was dreaming of creating my own SVG drawing class having SVG's inherited methods and then mine. As the wiser than me can foresee, the accompanying code spits out:

Can't locate object method "Foo" via package "SVG::Element" at ./test.
+pl line 17.

[download]

Of course, the message refers to the last line in Bar().

Does this mean I should mimic every SVG method I need into MyPackage (possibly by way of __SUPER__:: calls)? Or should I make $g behave as a MyPackage object by way of casting? Or? 

#!/usr/bin/perl

use warnings;
use strict;

package MyPackage;
use parent 'SVG';

sub Foo {
    my ($self, $fooArg) = @_;
    return $self->rectangle(id => $fooArg, x => 10, y => 10);
}

sub Bar {
    my ($self, $barArg) = @_;
    my $g = $self->group(id => $barArg);
    return $g->Foo("g$barArg");
}

package main;

my $s = MyPackage->new(); 

$s->Foo("someID");
$s->Bar("someOtherID");
print $s->xmlify(namespace => 'svg');

[download]

In reply to Extending a class by betacentauri

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