Support for some sort of collect()/extend() into `LinkedList<Vec<T>>` about rayon HOT 1 CLOSED

From what I can tell, building a LinkedList<Vec<T>> is an efficient (one of the more efficient?) ways of collecting a parallel iterator, which is why ParallelExtend for Vec uses it.

It's the most efficient way that we know, at least for unindexed iterators. For IndexedParallelIterator, we have a bit of pseudo-specialization (via opt_len) that lets it collect directly into the final pre-allocated Vec. We could still do that in your scenario as well, just slightly wastefully allocating a single LinkedList node to hold the entire Vec.

there could be a collect_vec_list() method on ParallelIterator, maybe.

I think that sounds reasonable!

I don't think we need an extend flavor though, because anyone can cheaply append a collection to an existing list.

from rayon.