Re: [boost] [in_place_factory] some suggestions for improvement

From: Tobias Schwinger (tschwinger_at_[hidden])
Date: 2007-04-04 05:28:31

Andrey Semashev wrote:
> Hello Tobias,
> 
> Tuesday, April 3, 2007, 9:02:45 PM, you wrote:
> 
>> Hi,
> 
>> in_place_factory can be quite useful, as I found out recently. However,
>> here are some suggestions to make it event better:
> 
>> 1. add a construction mechanism for arrays
> 
>> 2. add a note to the docs about deduction and using boost::ref
> 
>> 3. have the static 'apply' member function return the pointer to the 
>> constructed object - just like the placement new operator
> 
>> 4. use file iteration instead of BOOST_PP_REPEAT for maintainability
> 
> If I may, I'd like to add:
> 
> 5. add in_place_factory and typed_in_place_factory for zero
> constructor arguments. 

Quick discussion:

Often the reason against nullary function overloads is the earlier point 
of instantiation (nullary functions can't be templates), but that 
shouldn't be the problem here because 'in_place_factory's nested 'apply' 
is a template and 'typed_in_place_factory' is complete enough to be 
instantiated. For the 'inline in_place_factory0 in_place()' function the 
explicit 'inline' keyword is needed, however, not to break the ODR.

OK. It seems reasonable and it seems there are no unsolvable problems 
around, so let's add it ;-).

> I remember someone mentioned this before, but I
> can't remember any one answered.

That probably means that there's no maintainer. If that's so, I'd pick 
up this role.

Regards,
Tobias