[boost] [optional] memory use for optional refs and ptrs

Subject: [boost] [optional] memory use for optional refs and ptrs
From: Rutger ter Borg (rutger_at_[hidden])
Date: 2010-10-05 08:09:13

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?

Thanks,

Rutger