Implement heterogeneous count() for set

2022-01-03 13:35:07 -08:00
parent ccbe691cc8
commit 56f11f94d8
1 changed files with 12 additions and 0 deletions
--- a/include/boost/unordered/unordered_set.hpp
+++ b/include/boost/unordered/unordered_set.hpp
@ -500,6 +500,18 @@ namespace boost {

      size_type count(const key_type&) const;

+      template <class Key>
+      typename boost::enable_if_c<detail::are_transparent<Key, H, P>::value,
+        size_type>::type
+      count(const Key& k) const
+      {
+        node_pointer n = table_.find_node_impl(
+          table::policy::apply_hash(this->hash_function(), k), k,
+          this->key_eq());
+
+        return n ? 1 : 0;
+      }
+
      std::pair<const_iterator, const_iterator> equal_range(
        const key_type&) const;