If I have a map<key, value> some_map, can I create a vector of the keys also,
vector<key const &> ref_vec? I can create a vector<key const *> ptr_vec.
I'm thinking of my Bibtex data base of course.
/** All Bibliography keys derive from this base class, and need only define
* code() to be instantiated.
*/
class BibKey {
public:
enum Code {
BIBLIO_CODE,
BIBTEX_CODE
};
virtual ~BibKey() {}
virtual BibKey::Code code() const = 0;
std::string const & get() const { return key_; }
private:
std::string key_;
};
class BibtexKey : public BibKey {
public:
BibKey::Code code() const { return BibKey::BIBTEX_CODE; }
};
/** The BibTeX database stores a map of the data so,
* where Bibitem is the info
*/
typedef std::map<BibtexKey, Bibitem> BMap;
///
BMap data_;
/** But it also stores a vector of the keys to pass back to the
* citation dialog. Note that the citation dialog gets a vector of Bibkeys,
* not BibtexKeys or BiblioKeys.
*/
std::vector<BibKey const *> keys_;
Once I have the data, I can create the keys_, so:
keys_.resize(data_.size());
std::vector<BibKey const *>::iterator key_it = keys_.begin();
BMap::const_iterator map_it = data_.begin();
BMap::const_iterator map_end = data_.end();
for (; map_it != map_end; ++map_it, ++key_it) {
*key_it = &map_it->first;
}
But I can't do it if the keys_ is a vector of references, not pointers. Is
this impossible?
Angus
