Return a copy of the value associated with the specified key in a given
jss::concurrent_map object. If there is
no such value at the point of the call, insert one, as-if
and return a copy of that value.
DataType operator(KeyType const& key);
A copy of the value associated with
at the point of the call. If there is no such value, creates one
and returns a copy of the newly-constructed value.
Any exceptions thrown by the default constructor, copy constructor
or move constructor of
Any exception thrown by the application of the
may be called concurrently with any other member function of
jss::concurrent_map on a given instance
(except for the constructor and destructor) without external synchronization.