That's what I wanted to do: Blow away an entire subtree. Example: If I have

root
+--X1
|  +--Y1
|  |  +--Z1
|  |  \--Z2
|  |
|  +--Y2
[download]

and I'm currently in the root-node-handler, I may blow away all the Y's and everything below the Y's. So what I finally came up with is

  $t->purge_up_to($grandchild);
[download]

And yes you're right: It was a typo.