Re: [boost] Please don't define a fake "operator <" justfor ordered containers

From: Jody Hagins (jody-boost-011304_at_[hidden])
Date: 2006-07-10 17:31:28

On Mon, 10 Jul 2006 23:52:45 +0300
"Peter Dimov" <pdimov_at_[hidden]> wrote:

> Daryle Walker wrote:
> 
> > Looking at <http://www.boost.org/libs/smart_ptr/shared_ptr.htm>,
> > i.e. the Boost version, it seems that the authors fell into the
> > "fake operator <" trap.  If any of those authors are reading this,
> > can you tell us why you added the fake operator instead of a
> > custom-named comparison class?
> 
> shared_ptr defines operator< for map<shared_ptr<>, V> to work. What do
> you  mean by "fake"? 

I think that's what he means by "fake."  You defined an operator<() so
that it could be used with an STL container using the "default"
comparator, while providing a
shared-ptr-less-than-by-comparing-the-pointer comparator would be more
appropriate.

Of course, it would require passing the comparator instaed of using the
default std::less, but it does not introduce an operator<() that may not
be appropriate for some cases of shared_ptr<>.