export CMake variable to C++

[DungeonLords]

Inside my CMakeLists.txt I wrote

project(CMake_variable_to_code LANGUAGES CXX C DESCRIPTION "export CMake variable to C++ code example" VERSION 1.0.0.0)

How I can get CMake variables in C++ code? I want to get values: "CMake_variable_to_code", "export CMake variable to C++ code example", "1.0.0.0". And I also make suggestion to Qt to export variables from CMakeLists.txt

[DungeonLords]

I make code example for both ways. Here

[DungeonLords]

This is export CMake variable to C++ code example. I also use Qt but it is not a main point. In breaf

1. Inside CMakeLists.txt any project has something like

project(CMake_variable_to_code LANGUAGES CXX C DESCRIPTION "export CMake variable to C++ code example" VERSION 1.0.0.0)

2. Somewhere inside CMakeLists.txt you should add

add_compile_definitions(MYPROJECT_NAME=${PROJECT_NAME})
add_compile_definitions(MYPROJECT_DESCRIPTION=${PROJECT_DESCRIPTION})
add_compile_definitions(CMAKE_PROJECT_VERSION=${CMAKE_PROJECT_VERSION})

3. Then in C++ code you should add

#define Q(x) #x
#define QUOTE(x) Q(x)

4. Now you can use CMake's variables inside C++ code. For example

QCoreApplication::setApplicationName(QUOTE(MYPROJECT_NAME));
QCoreApplication::setApplicationVersion(QUOTE(CMAKE_PROJECT_VERSION));

See also my feature request for Qt project.

Compiling

git clone https://github.com/AndreiCherniaev/CMake_variable_to_code.git && cd CMake_variable_to_code
rm -rf build-host && mkdir build-host/
cmake -S src/ -B build-host/
cmake --build build-host/ --parallel

Test

build-host/CMake_variable_to_code --version
CMake_variable_to_code 1.0.0.0

build-host/CMake_variable_to_code --help
Usage: build-host/CMake_variable_to_code [options]
export CMake variable to C++ code example

Options:
  -h, --help     Displays help on commandline options.
  --help-all     Displays help, including generic Qt options.
  -v, --version  Displays version information.

See full-code repo.

[SimonSchroeder]

Here is a different approach from the official CMake tutorial: https://cmake.org/cmake/help/latest/guide/tutorial/A Basic Starting Point.html#exercise-3-adding-a-version-number-and-configured-header-file

[DungeonLords]

I make code example for both ways. Here