From: Brad Cox <bcox@...>
Date: 2002-04-13T07:46:41+09:00
Subject: Rudy idiom for enumeranting parents of a node?

I need to enumerate the parentage chain of the nodes in a 
doubly-linked tree. No problem in C/Java, but I'm still too new to 
Ruby to see how. Can someone help?

Here's  my first shot which doesn't work: compiler complains a block 
is expected after @parent.parent.

class Node
	def initialize(parent, children=[])
		@parent = parent
		@children = children
		@children.each { |child| child.parent(self) }
	end

	def parents
		@parent.parents unless @parent.nil?
		yield self
	end
end
--