"Chris" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED]
Hi
3) In this example, is t considered mutable or not? "Tuple are immutable" says the doc, but:t[0].append(0) t([1, 0], [2])
The tuple is immutable but its elements can be mutable: I tend to think that it means that the tuple is mutable. Indeed, it changed!
Well, it did and it didn't. If you went in and did an id() on each element, you'd discover that the actual objects didn't change: the exact same ids were in the exact same slots before and after. What you're seeing is the way the str() and repr() functions print the values of embedded objects, not the ids.
4) Even more confusing: I had the following strange result: (with both Python 2.3.3 and 2.4)t[0]+=[1]Traceback (most recent call last): File "<stdin>", line 1, in ? TypeError: object doesn't support item assignmentt([1, 0, 1], [2]) There was an exception, but the list was still changed!?
I consider that an error, but I've had several people tell me that it's the way it's supposed to be. I simply quit trying to get the point across. As far as I'm concerned, the behavior is simply wrong. Since mutating the object didn't change the id, it shouldn't try to replace the object in the tuple.
John Roth
Chris
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