How do I serialize and deserialize contents with std::deque in multithreaded code?

In multithreaded C++ applications, handling data serialization and deserialization effectively is crucial for ensuring that shared data structures like `std::deque` can be accessed safely by multiple threads. Below is a comprehensive guide that illustrates how to serialize and deserialize `std::deque` while maintaining thread safety.

#include <iostream>
#include <deque>
#include <mutex>
#include <fstream>
#include <sstream>

// Thread-safe wrapper for std::deque
template
class ThreadSafeDeque {
private:
    std::deque deque_;
    mutable std::mutex mutex_;

public:
    void push_back(const T &value) {
        std::lock_guard<:mutex> lock(mutex_);
        deque_.push_back(value);
    }

    void serialize(const std::string &filename) {
        std::lock_guard<:mutex> lock(mutex_);
        std::ofstream ofs(filename);
        for (const auto &item : deque_) {
            ofs << item << "\\n";
        }
        ofs.close();
    }

    void deserialize(const std::string &filename) {
        std::lock_guard<:mutex> lock(mutex_);
        std::ifstream ifs(filename);
        std::string line;
        while (std::getline(ifs, line)) {
            if (!line.empty()) {
                T item;
                std::istringstream iss(line);
                iss >> item; // Adjust parsing depending on T
                deque_.push_back(item);
            }
        }
        ifs.close();
    }

    void display() {
        std::lock_guard<:mutex> lock(mutex_);
        for (const auto &item : deque_) {
            std::cout << item << " ";
        }
        std::cout << std::endl;
    }
};

int main() {
    ThreadSafeDeque<int> tsDeque;
    tsDeque.push_back(1);
    tsDeque.push_back(2);
    tsDeque.push_back(3);
    
    tsDeque.serialize("deque_data.txt");
    
    ThreadSafeDeque<int> newDeque;
    newDeque.deserialize("deque_data.txt");
    newDeque.display();

    return 0;
}