Re: [boost] flyweight - gsoc idea - multikey-value flyweight

Subject: Re: [boost] flyweight - gsoc idea - multikey-value flyweight
From: Vicente J. Botet Escriba (vicente.botet_at_[hidden])
Date: 2016-02-17 12:52:28

Le 17/02/2016 08:11, Joaquin M LópezMuñoz a écrit :
> Vicente J. Botet Escriba <vicente.botet <at> wanadoo.fr> writes:
>
>> Le 16/02/2016 16:00, Joaquin M LópezMuñoz a écrit :
>>> Vicente J. Botet Escriba <vicente.botet <at> wanadoo.fr> writes:
>>>
>>>> Le 15/02/2016 07:51, Joaquin M LópezMuñoz a écrit :
>>> http://coliru.stacked-crooked.com/a/6dab2c556433fb03
>>>
>>> [...]
>>>
>>> * [...] the obvious drawback (among others) that
>>> sizeof(multi_flyweight)==2*sizeof(void*), where sizeof(flyweight) is
>>> typically sizeof(void*). Whether this is acceptable or not depends
>>> really on the use cases, I'd say.
>> No, I want really a fly weight. If I have N key the multi_flyweight will
>> not be fly weight anymore.
>>
>> sizeof(multi_flyweight)==N*sizeof(void*)
> No, this is not the case. sizeof(multi_flyweight)==2*sizeof(void*)
> for every N. The extra word is Boost.Variant's book-keeping data for
> type determination (internal member which_).
>   
My bad. I did a diagonal read of the code. This is already better. I 
believe that I could live with that even if I would prefer to spent only 
one pointer :)
>>> * Is this a desireable extension to Boost.Flyweight? I don't have a
>>> strong opinion myself, others' most welcome.
>> I have no problem if this is in another library or class. What interest
>> me is the functionality with the best performances in space and time.
> It'd be great if we can gauge potential interest besides your own.
You are right, if there is not interest we will lost a possible GSoC 
student.

Vicente