Dejan escribió:

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Or is a multi_index_container not the right tool?

Using Boost.MultiIndex might be overkill here if this is all you need from it: an std::set can be used also with a suitable compare predicate.

I don't know if finding pointer OR id is possible in a std::set. I've tried a std::set with a compare class (which compares pointer and id). To store is not a problem but to "container.find(pointer)" AND "container.find(id)".

OK, if you need to find elements by two different criteria then this is Boost.MultiIndex is designed for. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

Dejan escribió:

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typedef mi::multi_index_container< employee *, mi::indexed_by< mi::ordered_unique >

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employee_set;

Maybe i should mention that I search for something like this:

employee_set.find(employee* pointer);

and

employee_set.find(int id)

Now that I think again about it, when you write: employee* p=... employee_set.find(p); Can't you just write this employee* p=... employee_set.find(p->id); and be done with only one lookup criterion? Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

________________________________________ De: boost-users-bounces@lists.boost.org [boost-users-bounces@lists.boost.org] En nombre de Dejan [xamiw@arcor.de] Enviado el: miércoles, 03 de febrero de 2010 18:18 Para: boost-users@lists.boost.org Asunto: Re: [Boost-users] multi index container [solved]

Got it: [...]

That's right, but did you consider what I commented in my previous post? "Now that I think again about it, when you write: employee* p=... employee_set.find(p); Can't you just write this employee* p=... employee_set.find(p->id); and be done with only one lookup criterion?" Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

Dejan writes:

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That's right, but did you consider what I commented in my previous post?

Yeah, I did but the variable id is coming from outside (user) and not from inside (software). So p->id is never used.

The idea is to implement it the other way around, i.e. sorting by id: * When a user enters an id, you just look for it. * When the software has a pointer p to look for, it simply has to find(p->id) Clearer now?

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But I have again a problem. I can't get the member variable (like id in this example) directly. I have to use get_id(). When defining:

typedef multi_index_container < employee*, indexed_by < ordered_unique >,

// next line does not work ordered_unique >

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employee_set;

The code does not compile: error: ‘Employee::get_id() const’ cannot appear in a constant-expression error: a function call cannot appear in a constant-expression

You have to use const_mem_fun rather than member: http://www.boost.org/libs/multi_index/doc/tutorial/key_extraction.html#const... Joaquín M López Muñoz Telefónica, Investigación y Desarrollo