IO.md

Input

template<typename T>
[[nodiscard]]T input(const char* prompt = nullptr, bool retry = true);  //1
template<typename T>
[[nodiscard]]T input(const std::string& prompt, bool retry = true);     //2
template<typename T>
[[nodiscard]]T input(std::string_view prompt, bool retry = true);       //3

template<>
[[nodiscard]]std::string input(const char* prompt, bool retry = true);  //4
template<>
[[nodiscard]]std::string input(const std::string& prompt, bool retry);  //5
template<>
[[nodiscard]]std::string input(std::string_view prompt, bool retry);    //6

• 1-3 First print a message prompt, then get input from std::cin as if calling std::cin >> object; Returns the object of type T. If the operation is failing, it clears the error state of std::cin and returns either a default constructed object of type T or retry the whole process if retry flag is true.
• 4-6 First print a message prompt, then get input from std::cin as if calling std::getline. Returns the input string. If the string is empty and retry flag is true, it retry the whole process.

Output

template <char delim = ' ', std::ostream& os = std::cout, typename... Args>
void print(Args &&... args);    //1
template <std::ostream& os = std::cout, typename... Args>
void printLn(Args &&... args);  //2

1. Print any number of objects specified by the parameter pack args as if calling std::cout << args;, each followed by a delim. Print a new line after the call.
2. Equivalent to print<'\n'>(agrs...)

Thread Safe Output

Thread-safe output functions are static functions inside ThreadSafe class.

template<std::ostream& os = std::cout>
struct ThreadSafe
{
    template<char delim=' ', typename...Args>
    static inline void print(Args&& ...args);       //1

    template<char delim = ' ', typename...Args>
    static inline void tryPrint(Args&& ...args);    //2

    template<typename... Args>
    static inline void printLn(Args&&... args);     //3

    template<typename... Args>
    static inline void tryPrintLn(Args&&... args);  //4
};

• 1,3 is the thread-safe version of print and printLn, it blocks the current thread until it is able to print.
• 2,4 will try to lock the internal mutex and print. If the mutex is currently locked, it immediately returns without blocking.