Does associative array change the location of values?

Steven Schveighoffer schveiguy at
Sat Oct 30 11:59:15 UTC 2021

On 10/29/21 8:49 PM, Stanislav Blinov wrote:
> On Friday, 29 October 2021 at 21:00:48 UTC, Steven Schveighoffer wrote:
>> This is incorrect, the buckets are each heap allocated. Just the array 
>> of bucket pointers would change.
>> In addition, AAs do not deallocate the key/value pairs ever. You are 
>> safe to obtain a pointer to a value and it will stay there, even if 
>> you remove the key.
> Who's going to document these implementation details? ;) I mean, if no 
> one, then the above shouldn't be stated. Wouldn't you agree?

It should be documented. There isn't a valid way to remove these 
requirements, even if they are currently just an implementation detail 
-- code already depends on these properties. And D is a GC-based 
language, especially when using AAs. There is no reason to introduce 
undefined behavior for existing usage.

> Given the premise of the question at hand, it does seem useful to know 
> these. But at least one should stress what is and isn't subject to 
> change (even if unlikely).

The whole AA documentation probably needs some attention.


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