_This notebook is an adaptation of a lecture prepared by David Chamont (CNRS) under the terms of the licence [Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)](http://creativecommons.org/licenses/by-nc-sa/4.0/)_
_The present version has been written by Sébastien Gilles and Vincent Rouvreau (Inria)_
# [Getting started in C++](/) - [C++ in a real environment](/notebooks/6-InRealEnvironment/0-main.ipynb) - [TP 17](/notebooks/6-InRealEnvironment/2b-TP.ipynb)
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[This notebook](/notebooks/TP/HowTo.ipynb) explains very briefly your options to run the TP.
**WARNING:** Coliru is not an option here: you need to go the local or Docker way!
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### EXERCICE 52
### EXERCICE 43
Reorganize the project in several files:
- Only `loop()` and `main()` functions should remain in exercice52.cpp
- Exceptions should be separated in two files `Exception.cpp` and `Exception.hpp`.
-`PowerOfTwoApprox` will be put in two files: `PowerOfTwoApprox.hpp` and `PowerOfTwoApprox.hxx`. The latter will be included at the end of the former. You should also place in the same files the free functions that work closely with this class (e.g. `operator<<`).
**WARNING:** If you get complete template specializations, definition should be in a `cpp` file or inlined in header file!
- Do the same for the `TestDisplay` and its derived classes; you will need three files here (`cpp`, `hpp` and `hxx`).
- Finally, create two files `Tools.hpp` and `Tools.hxx` to put inside `times_power_of_2()`, `round_as_int` and `max_int`.
The provided CMake contains already the steps to make this work.
- Only `loop()` and `main()` functions should be put in _main.cpp_.
-`Error` should be declared in `Error.hpp` and defined in `Error.cpp`.
- Free functions such as `times_power_of_2` and `round_as_int` should be put in `Tools` files. As all these definitions are template, they should be in a header file (that might be the same as the one used for declaration, or a different one if you want to split declaration and definition - in this case don't forget to include it at the end of the hpp file!)
- Likewise for `PowerOfTwoApprox`. Closely related free functions (such as `operator<<`) should be put in the same file(s).
- You may put all `TestDIsplay` functionalities together. Beware: some definitions are template and must be in header files, whereas some aren't and should therefore be compiler.
To do the exercice, create an _Exercice43_ directory in the TP root (and include it in your main CMakeLists.txt).
Create the files in this directory, and use the following CMakeLists.txt:
````
add_library(exercice43_lib
SHARED
# Header files are not strictly necessary but may be useful for some CMake generators.
_This notebook is an adaptation of a lecture prepared by David Chamont (CNRS) under the terms of the licence [Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)](http://creativecommons.org/licenses/by-nc-sa/4.0/)_
_The present version has been written by Sébastien Gilles and Vincent Rouvreau (Inria)_
