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From: Joerg Walter (jhr.walter_at_[hidden])
Date: 2004-03-24 02:48:47

Hi Joaquin,

you wrote:

> I forgot to answer one of your questions. Here it comes:
> Joerg Walter < <at>> writes:
> > One more question: is there an (easy?) way to
> > iterate over the distinct values of an index
> You can do it as you would with a std::multiset:
> typedef indexed_set<...> indexed_t;
> typedef indexed_t::index_type<...>::type index_t;
> indexed_t iset;
> index_t& index=iset.get<...>();
> for(index::iterator it=index.begin();it!=index.end()){
> // do what you want to with the value
> // get next value
> it2=index.upper_bound(index.key_extractor()(*it));
> it=it2;
> }

Understood, a non_unique key has multi_set characteristics, whereas a unique
key has set characteristics.

> > (or to define the index as the
> > set of distinct values of the related attribute(s))?
> This would call for a new type of index, IHMO. Gotta
> think it over.

On a second thought: such a beast would be more of a view (losing the
relation to indexed_set's original data) and therefore possibly out of scope
for your library?


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