code: public <A extends Collection<? super ResultT>> A into(final A target) {
      forEach(new Block<ResultT>() {
        @Override
        public void apply(@Nonnull final ResultT t) {
          target.add(t);
        }
      });
      return target;
    }
docs: Iterates over all the documents, adding each to the given target.
  
  @param target the collection to insert into
  @param <A> the collection type
  @return the target