Re: [boost] Minimizing Dependencies within Generic Classes for Faster and Smaller Programs

Subject: Re: [boost] Minimizing Dependencies within Generic Classes for Faster and Smaller Programs
From: vicente.botet (vicente.botet_at_[hidden])
Date: 2010-11-14 07:59:44

----- Original Message ----- 
From: "Joaquin M Lopez Munoz" <joaquin_at_[hidden]>
To: <boost_at_[hidden]>
Sent: Saturday, November 13, 2010 1:37 PM
Subject: Re: [boost]Minimizing Dependencies within Generic Classes for Faster and Smaller Programs

> 3. With these caveats, Boost.MultiIndex iterators can be said
> to be SCARY as long as they belong to the same category
> of index (ordered, hashed, sequenced, random.access) in some
> situations, not in others. 
<snip>
> but the following, which would be far more useful, does
> *not* work:
> 
>  // example 2
> 
>  typedef multi_index_container<
>    int,
>    indexed_by<
>      ordered_unique<identity<int> >,
>      ordered_non_unique<identity<int>,std::greater<int> >
>    >
>  > multi_t;
> 
>  multi_t::nth_index<0>::type::iterator it1;
>  multi_t::nth_index<1>::type::iterator it2;
> 
>  it1=it2;

I can see the utility of these kind of assignments, but I would not name them SCARY, as the types are different. I find however enough clear the approach you take in Boost.MultiIndex to achieve the same behavior via projections

http://www.boost.org/doc/libs/1_44_0/libs/multi_index/doc/tutorial/basics.html#projection

Best,
Vicente