I can't understand an error about INTERFACE_SOURCES and prefix

Thanks for your answer. It’s great that the author of this article takes place.

I’m off for now. It is the evening here.
The main difference with your project is that my library is splitted in several sublibraries (but there is only one binary at the end). So I have several subdirectories in my include directories. I had to use the loop, and to some adjustments (probably in a wrong way).

An other difference is that I have a test application in my project.

So I have something like that :

└── MyLibrary
    ├── CMakeLists.txt
    ├── include
    │   └── MyLibrary
    │       ├── SubLib1
    │       │   └── b.h
    │       ├── SubLib2
    │       │   └── c.h
    │       └── SubLib3
    │           └── d.h
    ├── src
    │   ├── CMakeLists.txt
    │   ├── SubLib1
    │   │   ├── a.h
    │   │   ├── a.cpp
    │   │   └── b.cpp
    │   └── SubLib3
    │       └── d.cpp
    └── test
        ├── CMakeLists.txt
        └── test.cpp

Buf for the CMakeLists.txt, you’ll have to wait some hours I came back to my office !