print Audio::TagLib::ID3v2::Frame::size(1), "\n";

##</code><code>##

THIS is not of type Audio::TagLib::ID3v2::Frame

##</code><code>##

unsigned int 
TagLib::ID3v2::Frame::size()
CODE:
	RETVAL = THIS->size();
OUTPUT:
	RETVAL

##</code><code>##

...
if (sv_isobject(ST(0)) && sv_derived_from(ST(0), "Audio::TagLib::ID3v2::Fram
        THIS = INT2PTR(TagLib::ID3v2::Frame *, SvIV((SV *)SvRV(ST(0))));
    else
        Perl_croak(aTHX_ "THIS is not of type Audio::TagLib::ID3v2::Frame");