par_iter only over ways

[Stunkymonkey]

is there another maybe faster way to iterate only over all ways
from the documentation i got this:

for block in pbf.blobs().map(|b| primitive_block_from_blob(&b.unwrap())) {
        let block = block.unwrap();
        for group in block.get_primitivegroup().iter() {
            for way in groups::ways(&group, &block) {

using par_iter on all objects is okay, but this is faster. is there also an par_iter for the groups?