our $AUTOLOAD;
sub AUTOLOAD {
    my( $self )= shift @_;
    my( $class, $method )= $AUTOLOAD =~ /^(.+)(?:'|::)(.+)$/
        or  die "Invalid method name: $AUTOLOAD";
    return
        if  'DESTROY' eq $method;
    die "Can't call internal method, $method, via ", __PACKAGE__, $/
        if  $method =~ /^_/;
    return $self->{whatever}->$method( @_ );
}
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Not so much "proper" or "elegant" but a thrown-together example but also not "improper" nor particularly "inelegant".