std::print() wrapper with altered format

zaasmi — Invalid Date

@zaasmi said in std::print() wrapper with altered format: Here’s a rewritten version of your question: “I’m trying to create a std::print() wrapper that modifies the output format, such as adding a prefix and suffix around the original format. I was able to achieve this using a macro. How can I improve this approach or implement it differently for more flexibility?” #define DECORATED_PRINT(fmt, ...) std::println("prefix " fmt " suffix", __VA_ARGS__) To achieve a std::print() wrapper with a modified format (e.g., adding a prefix and suffix), using a macro is one way, but there are other approaches that might offer more flexibility and better maintainability. Here are a few options: Using a Macro You can use a macro to wrap std::print() and modify the format. Here’s a simple example: #define PRINT_WITH_FORMAT(fmt, ...) std::print("[Prefix] " fmt " [Suffix]\n", ##__VA_ARGS__) While this works, macros have limitations in terms of type safety, debugging, and maintainability, especially for larger projects. Using a Function Template For more flexibility, you can create a function template that wraps std::print() and modifies the format. This way, you avoid the pitfalls of macros while still achieving the same goal: #include #include template void print_with_format(const std::string& fmt, Args&&... args) { std::string formatted_message = std::format("[Prefix] " + fmt + " [Suffix]\n", std::forward(args)...); std::cout << formatted_message; } Usage: print_with_format("Hello, {}!", "World"); Custom Formatter (Advanced) If you want more control over the formatting process, you can create a custom formatter by extending std::formatter: #include #include template <> struct std::formatter { constexpr auto parse(auto& ctx) { return ctx.begin(); } auto format(const std::string& s, auto& ctx) { return std::format_to(ctx.out(), "[Prefix] {} [Suffix]", s); } }; void print_with_format(const std::string& message) { std::cout << std::format("{}", message) << '\n'; } This approach gives you deep customization over how different types are formatted. Conclusion • Macros are quick and simple but have limitations in flexibility and maintainability. • Function templates offer a more modern, type-safe, and maintainable solution. • Custom formatters provide advanced control and customization, especially for complex formatting needs. For most use cases, the function template approach strikes a good balance between flexibility and simplicity.

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std::print() wrapper with altered format