Modern C++ exercises

Compilation and running the project

Check your g++ version by typing: > g++ --version It should be >= 7.0

> mkdir build
> cd build
> cmake ..
> make
> ./modern_cpp

Or use QT Creator... (or other IDE).

Tasks:

1. nullptr: Change all NULL to nullptrs
2. using alias: Change typedef to using alias
3. Scoped enum: Write a new scoped enum named Color and define in it 3 colors of your choice. Inherit from unsigned char. Add a new field: Color color in the Shape class, so that every shape has it's own defined color.
4. auto: Use auto, wherever you should.
5. Range-based for loop: Use range-based for loops, wherever possible.
6. default, delete: Mark copy constructors as default. Delete getY() method in Square and all default constructors of shapes
7. final, override: Mark Circle class as final Mark getX() in Rectangle as final. What is the problem? Mark all overridden virtual methods. Can you spot the problem?
8. constexpr: Write a function that calculates n-th Fibonacci's number. Do not mark it constexpr. In the first line of main() add computing 45-th Fibonacci's number. Measure the time of program execution (time ./modern_cpp) Mark fibonacci function as constexpr, compile the program and measure the time of execution once again. If you can't see a big difference assign the result to the constexpr variable.
9. Uniform initialization: Use initializer_list to initialize the collection. Add a new constructor to Shape - Shape(Color c). What happens? Use constructor inheritance to allow initialization of all shapes providing only a Color as a parameter. Create some shapes providing Color only param. Add in-class field initialization for all shapes to safely use inherited constructor.
10. Lambda functions: Change functions from main.cpp into lambdas (sortByArea, perimeterBiggerThan20, areaLessThan10) Change lambda areaLessThan10 into lambda areaLessThanX, which takes x = 10 on a capture list. What is the problem? Use std::function to solve the problem.

Homework:

1. Attributes: Add a new method double getPi() in Circle class, which returns a PI number. Mark it as deprecated.
2. noexcept: Mark some getArea() and getPerimeter() methods as noexcept
3. Move semantics: Add move constructors and move assignment operators to all shapes. Mark them as noexcept. What about Rule of 5? Move some shapes into the collection.
4. Delegating constructors: Add a new constructor, which takes also the previously defined Color of a shape. You can use a default parameter for Color. Delegate a call in the old constructor to the new one.
5. Variadic templates: Write a factory method which should work like std::make_shared. It should have below signature:

   template<class DerivedType, class... Arguments>
   std::shared_ptr<Shape> make_shape(Arguments&&... args);

   Inside, it should create a shared_ptr to DerivedType and pass all arguments into constructor of DerivedType via perfect forwarding.