struct IDCompare
{
bool operator()(const IdentifiablePtr& lhs, const IdentifiablePtr& rhs) const
{
return strcmp(lhs->Id().c_str(), rhs->Id().c_str()) < 0 ;
}
};
std::set<boost::shared_ptr<SomeType>, IDCompare>
template<typename T>
boost::shared_ptr<T> Find(const std::string& id) const
{
boost::shared_ptr<T> dummy(new T(id));
SetType::const_iterator it = mySet.find(dummy);
return it != Get<T>().end() ? *it : boost::shared_ptr<T>();
}
return strcmp(lhs->Id().c_str(), rhs->Id().c_str()) < 0 ; return lhs->Id() < rhs->Id();Quote:Original post by visitorreturn strcmp(lhs->Id().c_str(), rhs->Id().c_str()) < 0 ;
This would be somewhat simpler as:return lhs->Id() < rhs->Id();
As to the dummy, at least it doesn't have to be allocated dynamically. But perhaps a map would be better (do the objects even need to know their ID if the map could know that?)
Quote:Original post by Dragon_StrikeWhat kinds of problems? It's just that it seems relatively easy to extract the value from a key-value pair?
there are problems when i want to use algorithms on the collection... since the map iterator works on key value pairs
Quote:Original post by incin
struct IDCompare
{
bool operator()(const IdentifiablePtr& lhs, const IdentifiablePtr& rhs) const
{
return lhs->Id() < rhs->Id();
}
bool operator()(const IdentifiablePtr& lhs, const std::string& rhs) const
{
return lhs->Id() < rhs;
}
bool operator()(const std::string& lhs, const IdentifiablePtr& rhs) const
{
return lhs < rhs->Id();
}
};
...
std::string str("hi");
mySet.find(str);
Quote:Original post by dmatterQuote:Original post by Dragon_StrikeWhat kinds of problems? It's just that it seems relatively easy to extract the value from a key-value pair?
there are problems when i want to use algorithms on the collection... since the map iterator works on key value pairs
Quote:
But it obviously won't work, as find() must take a value_type.
