Re: [boost] [unnullable_ptr] Proposal for a new library

From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2008-07-23 19:29:14

AMDG

Mathias Gaunard wrote:
>> So (if I understand you correctly), you want not function-pointer
>> behaviour,
>> but something more like reference - have to be initialized, cannot be null?
>>     
>
> Well yeah, preventing an "empty" state means that you have to initialize
> the thing, it cannot be null.
> That's what the whole thread is about.
>   

I don't think that boost::function should provide a never empty guarantee
for several technical reasons:
a) Providing the guarantee has a runtime cost.  Allowing
    empty Boost.Function objects is free.
b) Looking forward to C++0x, it is impossible to implement a
    no throw move for objects than have no empty state.
c) Objects that provide default constructors are easier to work with.

In Christ,
Steven Watanabe