Re: Weird irreproducible error

[Steve Heller <steve@...>]

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