Default HashCompare for concurrent_hash_map.
template<typename Key> struct tbb_hash_compare;
#include "tbb/concurrent_hash_map.h"
A tbb_hash_compare<Key> is the default for the HashCompare argument of template class concurrent_hash_map. The built-in definition relies on operator== and tbb_hasher as shown in the Members description. For your own types, you can define a template specialization of tbb_hash_compare or define an overload of tbb_hasher.
There are built-in definitions of tbb_hasher for the following Key types:
Types that are convertible to a size_t by static_cast<T>
Pointer types
std::basic_string
std::pair<K1,K2> where K1 and K2 are hashed using tbb_hasher.
namespace tbb {
template<typename Key>
struct tbb_hash_compare {
static size_t hash(const Key& a) {
return tbb_hasher(a);
}
static bool equal(const Key& a, const Key& b) {
return a==b;
}
};
template<typename T>
size_t tbb_hasher(const T&);
template<typename T>
size_t tbb_hasher(T*);
template<typename T, typename Traits, typename Alloc>
size_t tbb_hasher(const std::basic_string<T, Traits,Alloc>&);
template<typename T1, typename T2>
size_t tbb_hasher(const std::pair<T1,T2>& );
};