cbeam/container/stable_interprocess_map.hpp

Updates an existing entry in the map or inserts a new one if the key does not exist.

Updates an existing entry in the map or inserts a new one if the key does not exist.This method abstracts the common pattern of checking for an existing key, updating its value if present, or inserting a new key-value pair if the key is not found. The method handles locking, deserialization, and serialization of the map internally.

Parameters

key	The key to update or insert.
updater	A function that updates the value associated with the key. It takes a reference to the value type.
default_value	The default value to insert if the key is not found in the map.

stable_interprocess_map<int, std::string> myMap("my_shared_memory", 1024);
myMap.update_or_insert(42, [](std::string& value) { value += " updated"; }, "default value");