TYPEMAP
head * O_OBJECT
OUTPUT
O_OBJECT
sv_setref_pv( $arg, "Table::ParentChild::Head", (void *)$var );
INPUT
O_OBJECT
if( sv_isobject( $arg ) && (SvTYPE(SvRV($arg)) == SVt_PVMG)) {
$var = ($type) SvIV((SV*)SvRV($arg));
} else {
warn( \"${Package}::$func_name() -- $var is not a blessed SV reference\" );
XSRETURN_UNDEF;
}