(Changed in version 2.9.0) The behavior of scanRight has changed. The previous behavior can be reproduced with scanRight.reverse.
(Changed in version 2.9.0) transpose throws an IllegalArgumentException if collections are not uniformly sized.
The
/g_headmessage pair-wise places nodes at the head of groups./g_head [ Int - the ID of the group at which head a node is to be placed (B) int - the ID of the node to place (A) ] * NSo that for each pair, node A is moved to the head of group B.