[ZODB-Dev] BTrees Bug?

[Dieter Maurer]

Chris Withers wrote at 2005-2-2 14:59 +0000:
> ...
> >>> for key in b.keys(0,3):
>...   print key
>...   del b[key]
>...
>0
>2
> ...
>2. The above feels like a bug to me, even excluding the common pythonism 
>of not being able to iterate over mutables if you're changing them. The 
>above code is saying "gimme keys where the key is less that 3", which it 
>doesn't do :-S

This is not at all BTree specific.

You get similar behaviour with a list:

    for x in some_list:
	some_list.remove(x)

The Python documentation clearly documents this caveat (for lists)
and suggests the right work around: copy the list before you
iterate destructively over it.

In your concrete example: this would read:

   for key in list(b.keys(0,3)): ...

-- 
Dieter