Re: [Boost-users] Multi-index container (Modifying non-unique key in the container)

From: Ramesh (rramesh1_at_[hidden])
Date: 2008-08-29 17:08:02

On Sun, Aug 24, 2008 at 2:55 PM, JOAQUIN M. LOPEZ MUÑOZ <joaquin_at_[hidden]>wrote:

>  (Excuse the slow pace of this thread, I've been on vacation with little
> access to the Internet).
>
>  ------------------------------
> *De:* boost-users-bounces_at_[hidden] [
> boost-users-bounces_at_[hidden]] En nombre de Ramesh [
> rramesh1_at_[hidden]]
> *Enviado el:* jueves, 21 de agosto de 2008 0:17
> *Para:* boost-users_at_[hidden]
> *Asunto:* Re: [Boost-users] Multi-index container (Modifying non-unique
> key in the container)
>
>
>  On Wed, Aug 20, 2008 at 8:02 AM, JOAQUIN M. LOPEZ MUÑOZ <joaquin_at_[hidden]>wrote:
>
>>
>> Yes, but DataMap seems to *replicate* the keys that are already
>>  present in A. Cannot you just have the following?
>>
>> typedef multi_index_container<
>>   A*,
>>     indexed_by<
>>         ordered_unique<
>>             tag <Key1>, BOOST_MULTI_INDEX_MEMBER(A,std::string,Key1)>,
>>         ordered_non_unique<
>>                   tag<Key2>,BOOST_MULTI_INDEX_MEMBER(A,long,Key2)>,
>>               ordered_unique<
>>                   tag<Key3>,BOOST_MULTI_INDEX_MEMBER(A,long,Key3)>
>>     >
>> > tDMap;
>>
>> [...]
>> >
>>
>>
>>
>   > If I would remove the keys the map would just hold pointers and I
> wouldnt be able to
> > do lookups based on the keys (to retrieve pointers to objects based on
> keys) if I wouldnt
> > pair the pointers with they keys in the Map - thats why I have the keys
> in the map, please
> > correct me if am wrong.
>  You can use the members of the pointed to objects of type A as keys of
> your container.
> This is discussed in detail at:
>
>
> http://www.boost.org/libs/multi_index/doc/reference/key_extraction.html#chained_pointers
>
> In particular, I think that the tDMap definition I gave above should work
> directly. Please
> report back if this is not the case.
>
> Joaquín M López Muñoz
> Telefónica, Investigación y Desarrollo
>
> _______________________________________________
> Boost-users mailing list
> Boost-users_at_[hidden]
> http://lists.boost.org/mailman/listinfo.cgi/boost-users

My turn to ask you for excuse :)

Didnt get a chance to come back to you real quick on this. I dug up the
thread archive on multi-index,  after seeing your note , found holle.cpp,
found it very comprehensive. It does explain pretty much all of multi-index
capabilities.
Thanks a bunch correcting the data structure. I dont think I need to keep
the keys inside the map.

Regards
Ramesh