Reasonable CMake For C++ Demos

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reason.cmake is a CMake wrapper to enhance the build experience for C++.

Project 1

It shows how to integrate reason.cmake with legacy CMake modules, using add_subdirectory.

The module1 and module2 in the deps directory are written completely in native CMake code without any 'reason' integration.

Using legacy modules is risky and buggy because previous CMakeLists.txt might damage the whole build via setting global include directories and global compile options. Any failed module should be manually converted into reason build, and you will get the benefits from now on.

Project 2

It shows how to depend on an external reason build project. (Project 2 depends on Project 1)

By showing cmake where the Project 1 is installed via CMAKE_PREFIX_PATH variable, you can use find_package seamlessly.

Note:

1. If you have already installed Project1 by package manager, aka. dpkg installed globally into /usr/ directory, the global path is already in CMAKE_PREFIX_PATH, and there's no extra work at all.
2. The package built (i.e. deb package) does not include files in Project 1 or any other packages found via find_package, and therefore both packages are required at binary distribution.

Project 3

It shows how to rewrite Project 1 with reason.cmake.

Project 4

It shows how to integrate with header-only libraries, or named 'interface libraries' in CMake.

Project 5

It shows how multiple executables depend on common libraries are managed in reason.cmake.