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Subject: Re: [boost] [optional] memory use for optional refs and ptrs
From: John Reid (j.reid_at_[hidden])
Date: 2010-10-05 09:42:58


Rutger ter Borg wrote:
>
> Hello,
>
> I'm looking into boost::optional<> as a replacement for some of my code
> which has to deal with optional values. However, it seems that cases
> which are usually space-efficient optionals (e.g., ptrs in the form of a
> null-ptr) do not have template specializations. In other words, boost
> optional templates store a bool and the memory footprint of its template
> parameter, regardless of type. I.e., optional references and pointers
> take their space plus the space of an extra bool.
>
> Is there a reason for this?
>
Might someone want to store a null pointer in the optional? I'm not sure
about the references though.

John.


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