On Fri, Jan 9, 2009 at 10:15 PM, Justin <fatcat1...@gmail.com> wrote:
> However when I attempt to convert preorder() to a generator and
> iterate over the results things don't go as planned:
>
> def preorder(tree, index, path=[]):
> if index >= len(tree): return
> path = path + [tree[index]]
> yield path
> preorder(tree, left(index), path)
> preorder(tree, right(index), path)
You have to explicitly loop over and yield the results of the
recursive calls; there is no automatic machinery or shortcut for this:
def preorder(tree, index, path=[]):
if index >= len(tree): return
path = path + [tree[index]]
yield path
for path in preorder(tree, left(index), path):
yield path
for path in preorder(tree, right(index), path):
yield path
You may want to yield just the individual path elements, not the full
path, at each step.
Kent
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