Ok. Question was from Martin.
What behaviour we want from WeakValueDictionary for garbaged values?
dictionary := WeakValueDictionary with: 'hello' -> 'world' copy.
> Smalltalk garbageCollect.
> {
> dictionary values includes: nil.
> dictionary at: 'hello'.
> dictionary at: 'hello' ifAbsent: [ 'absent' ].
> dictionary at: 'hello' ifAbsentPut: [ 'put' ].
> }
> is:
> #(true nil nil nil)
My opinion is: it should work in same way when 'hello' item is absent.
It is intuitive for me and It would be consistent to WeakSet behaviour:
set := WeakSet with: Object new.
Smalltalk garbageCollect.
set includes: nil "=>false"
But after writing it I realized how much WeakSet is inconsistent:
set := WeakSet with: Object new.
Smalltalk garbageCollect.
set isEmpty. "=>false"
set size. "=>1".
set anyOne. "=> nil"
set includes: nil. "=>false"
set collect: #yourself. "=>a WeakSet()"
We definitely have something to improve here.
2017-02-21 13:36 GMT+01:00 Guillermo Polito <guillermopol...@gmail.com>:
> Everything has a tradeoff. I do not understand the question.
>
> On Tue, Feb 21, 2017 at 1:19 PM, Denis Kudriashov <dionisi...@gmail.com>
> wrote:
>
>>
>> 2017-02-21 13:07 GMT+01:00 Guillermo Polito <guillermopol...@gmail.com>:
>>
>>> But in any case, whatever the alternative you give users, they must
>>> understand the tradeoff. If all Weak*Dictionaries were subscribed by
>>> default to the weak registry for cleanup, that would provoke a lot of
>>> overhead during garbage collection.
>>>
>>
>> So you think my suggestion for implementation will lead to some tradeoff?
>> What exactly? (if yes).
>>
>
>
