Re: Weird irreproducible error
[
Date Prev][
Date Next][
Thread Prev][
Thread Next]
[
Date Index]
[
Thread Index]
- Subject: Re: Weird irreproducible error
- From: Steve Heller <steve@...>
- Date: 2007年10月08日 08:24:02 -0500
On Mon, 8 Oct 2007 13:50:55 +0100, David Jones <drj@pobox.com> wrote:
>On 7 Oct 2007, at 13:30, Steve Heller wrote:
>
>
>> On Sun, 7 Oct 2007 06:25:22 -0600, "Patrick Donnelly"
>> <batrick.donnelly@gmail.com> wrote:
>>
>>
>>> Could be you're expecting pairs() to do the same order every time,
>>> even with the same data input every time.
>>>
>>
>> I don't think that is the problem. I don't rely on the order of
>> pairs() at all, as far as I know.
>>
>> I do wonder though: why wouldn't pairs() produce the same order, with
>> the same data and script(s)?
>>
>
>a) because it's allowed to by the documentation; and,
>
>b) because hash tables use address-based hashing (for keys that are
>themselves tables), so the order of pairs() depends on where in
>memory the tables (that are keys) got allocated. That can change
>either on a whim or, perhaps more likely, when DLLs have been mapped
>into different places in the address space (thus meaning the holes
>left for memory allocation are different).
Very interesting. Thanks!
Steve