BloombergLP::bslalg::HashTableImpUtil::extractKey

Return a reference providing non‐modifiable access to the key (of type KEY_CONFIG::KeyType) held by the specified link. The behavior is undefined unless link refers to a node of type BidirectionalNode<KEY_CONFIG::ValueType>. KEY_CONFIG shall be a namespace providing the type names KeyType and ValueType, as well as a function that can be called as if it had the following signature: ` const KeyType& extractKey(const ValueType& obj); `