TYPEMAP
struct attrl *        	      T_PTROBJ

OUTPUT
T_PTROBJ
        sv_setref_pv( $arg, CLASS, (void*)$var );

INPUT
T_PTROBJ
        if( sv_isobject($arg) && (SvTYPE(SvRV($arg)) == SVt_PVMG) ){
                $var = ($type)SvIV((SV*)SvRV( $arg ));
        }else{
                XSRETURN_UNDEF;
        }