docs: def enumiter(self, other, rmax, bunch=100000):
          """ cross correlate with other, for all pairs
              closer than rmax, iterate.
  
              for r, i, j in A.enumiter(...):
                  ...
              where r is the distance, i and j are the original
              input array index of the data.
  
              This uses a thread to convert from KDNode.enum.
          """
  
          def feeder(process):
              self.enum(other, rmax, process, bunch)
          for r, i, j in makeiter(feeder):
              yield r, i, j