Python list recursion type error
- by Jacob J Callahan
I can't seem to figure out why the following code is giving me a TypeError: 'type' object is not iterable
pastebin: http://pastebin.com/VFZYY4v0
def genList(self):
#recursively generates a sorted list of child node values
numList = []
if self.leftChild != 'none':
numList.extend(self.leftChild.genList()) #error
numList.extend(list((self.Value,)))
if self.rightChild != 'none':
numList.extend(self.rightChild.genList()) #error
return numList
code that adds child nodes (works correctly)
def addChild(self, child):
#add a child node. working
if child.Value < self.Value:
if self.leftChild == 'none':
self.leftChild = child
child.parent = self
else:
self.leftChild.addChild(child)
elif child.Value > self.Value:
if self.rightChild == 'none':
self.rightChild = child
child.parent = self
else:
self.rightChild.addChild(child)
Any help would be appreciated.
Full interpreter session:
>>> import BinTreeNode as BTN
>>> node1 = BTN.BinaryTreeNode(5)
>>> node2 = BTN.BinaryTreeNode(2)
>>> node3 = BTN.BinaryTreeNode(12)
>>> node3 = BTN.BinaryTreeNode(16)
>>> node4 = BTN.BinaryTreeNode(4)
>>> node5 = BTN.BinaryTreeNode(13)
>>> node1.addChild(node2)
>>> node1.addChild(node3)
>>> node1.addChild(node4)
>>> node1.addChild(node5)
>>> node4.genList()
<class 'list'>
>>> node1.genList()
Traceback (most recent call last):
File "<interactive input>", line 1, in <module>
File "C:...\python\BinTreeNode.py", line 47, in genList
numList.extend(self.leftChild.genList()) #error
File "C:...\python\BinTreeNode.py", line 52, in genList
TypeError: 'type' object is not iterable
