pub macro link(
        impl simulate < $__g_0:ty, $__g_1:ty, $__g_2:ty, $__g_3:ty, $__g_4:ty,
        $__g_5:ty, $__g_6:ty, $__g_7:ty, $__g_8:ty, $__g_9:ty, $__g_10:ty,
        $__g_11:ty, $__g_12:ty, $__g_13:ty $(,)? > for $ptx:ident
    ) {
    ...
}