Data update

Task/Constrained-genericity/C++/constrained-genericity-1.cpp

@@ -0,0 +1,13 @@
+template<typename T> concept Eatable = requires(T t) { t.eat(); };
+
+struct Potato { void eat(); };
+
+struct Brick {};
+
+template<Eatable T> class FoodBox {};
+
+int main() {
+    FoodBox<Potato> lunch{};
+    // Following leads to compile-time error
+    //FoodBox<Brick> practical_joke{};
+}

Task/Constrained-genericity/C++/constrained-genericity-2.cpp

@@ -1,5 +1,5 @@
-template<typename T> //Detection helper struct
-struct can_eat       //Detects presence of non-const member function void eat()
+template<typename T> // Detection helper struct
+struct can_eat       // Detects presence of non-const member function void eat()
 {
   private:
     template<typename U, void (U::*)()> struct SFINAE {};