{fmt} VS spdlog

it's probably not chrome because they are using this third party library: (https://github.com/fmtlib/fmt). also, it might be that this sink is actually meant to write a message to the console but due to configuration options its a noop.

Some people are noticing that println is very new. But there already is https://github.com/fmtlib/fmt and it has been there quite a long time.

It was emulated using horrible macros: https://github.com/fmtlib/fmt/blob/8f5e07656e25ec64ec7c843f0.... IIRC some early versions of `std::tuple` did something similar.

Continuation passing monads form the basis of a perfectly valid and usable software architecture and programming pattern.

In the case of ostream and operator<<, this pattern reduces the number of intermediate objects that would otherwise be constructed.

If you object to iostream on religious or stylistic grounds, there's always fmt which is more like Go or Python string interpolation.[0]

0. https://fmt.dev

GitHub repo: fmtlib/fmt

cmake_minimum_required(VERSION 3.5) project(knn_cpp CXX) # Set up C++ version and properties include(CheckIncludeFileCXX) check_include_file_cxx(any HAS_ANY) check_include_file_cxx(string_view HAS_STRING_VIEW) check_include_file_cxx(coroutine HAS_COROUTINE) set(CMAKE_CXX_STANDARD 20) set(CMAKE_BUILD_TYPE Debug) set(CMAKE_CXX_STANDARD_REQUIRED ON) set(CMAKE_CXX_EXTENSIONS OFF) # Copy data file to build directory file(COPY ${CMAKE_CURRENT_SOURCE_DIR}/iris.data DESTINATION ${CMAKE_CURRENT_BINARY_DIR}) # Download library usinng FetchContent include(FetchContent) FetchContent_Declare(matplotplusplus GIT_REPOSITORY https://github.com/alandefreitas/matplotplusplus GIT_TAG origin/master) FetchContent_GetProperties(matplotplusplus) if(NOT matplotplusplus_POPULATED) FetchContent_Populate(matplotplusplus) add_subdirectory(${matplotplusplus_SOURCE_DIR} ${matplotplusplus_BINARY_DIR} EXCLUDE_FROM_ALL) endif() FetchContent_Declare( fmt GIT_REPOSITORY https://github.com/fmtlib/fmt.git GIT_TAG 7.1.3 # Adjust the version as needed ) FetchContent_MakeAvailable(fmt) # Add executable and link project libraries and folders add_executable(${PROJECT_NAME} main.cc) target_link_libraries(${PROJECT_NAME} PUBLIC matplot fmt::fmt) aux_source_directory(lib LIB_SRC) target_include_directories(${PROJECT_NAME} PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}) target_sources(${PROJECT_NAME} PRIVATE ${LIB_SRC}) add_subdirectory(tests)

Good catch, thanks! Fixed now. This explains why the difference was kinda low compared to another benchmark: https://github.com/fmtlib/fmt?tab=readme-ov-file#compile-tim....

> This is from C++23, right?

std::println is, yes.

> I wonder how available this is within compilers

https://en.cppreference.com/w/cpp/compiler_support says clang, gcc, and msvc all support it, though I don't know how recent those versions are off the top of my head.

In my understanding, with this specific feature, if you want a polyfill for older compilers, or to use some more cutting-edge features that haven't been standardized yet, https://github.com/fmtlib/fmt is available to you.

Why a new lib instead of using or contributing to an existing one as spdlog?

https://github.com/gabime/spdlog

GitHub repo: gabime/spdlog

SpdLog https://github.com/gabime/spdlog

The usual recommendation when logging libraries are brought up is spdlog, which is however header-only. It's available on Conan-center.

* Aha! In digging up the docs for NDC, I found this[1], which does mention a book for your reading list: "Patterns for Logging Diagnostic Messages" part of the book "Pattern Languages of Program Design 3" edited by Martin et al.

[1] https://github.com/gabime/spdlog

FetchContent_Declare( spdlog GIT_REPOSITORY https://github.com/gabime/spdlog GIT_TAG origin/v1.x ) FetchContent_MakeAvailable(spdlog)

Typically, you'd use a logging library to handle stuff like this. I personally like spdlog. You use different logger functions (info, warn, error) and depending on what level you have set for the logger (or globally) some of the functions become no-ops. E.g. When not running in verbose mode all spdlog::info() do nothing.