Remove algo duplication

[Paolo Carlini]

Hi,

On 09/16/2013 10:46 PM, Marc Glisse wrote:
> On Mon, 16 Sep 2013, Paolo Carlini wrote:
>
>> On 09/16/2013 04:54 PM, Marc Glisse wrote:
>>> By the way, I thought someone had contributed less<void> and the 
>>> others already, but I can't see them. Did I imagine that patch?
>> Humm, I guess so :-) Jon has definitely some work in the making but I 
>> don't think he mentioned it. Thus, I suppose we are looking for 
>> volunteers ;)
> How much do you hate macros? What would you think of something like 
> this (with better macro names)? Does this C++03 emulation even make 
> sense?
> (not sure how to handle doxygen with this)
Well, for sure we already have quite a bit of macros in the allocator 
area. I wish Jon could also give his opinion... I'm not sure however to 
understand in detail how much of this is just helper code for the algo 
duplication work, and how much is implementation of standard facilities. 
I suppose however, that we should cleanly separate the C++11 code from 
the C++98 emulation and have the latter only in predefined_ops.h or 
something.

In terms of details, we are trying not to use the deprecated 
unary_function / binary_function, not even as implementation details. In 
fact if we find ourselves often doing that, I don't see why we 
deprecated the facilities ;) Anyway, I seem to remember that there are 
concrete issues, like deprecated warnings in some cases aren't 
completely shut up in system headers, etc. Let's try to avoid those.

Paolo.