PI06 i PI06-1. Docker definitions for MSSQL and Postgres. Data seeder/generator for countries and people. Entity Framework example with variants for Postgres and MSSQL

SomeOfCSharpFeatures/CovarianceContravariance/Program.cs

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+using Inheritance;
+
+namespace CovarianceContravariance;
+
+class Program
+{
+  static void Main(string[] args)
+  {
+    List<Car> cars = new List<Car>{
+      new Car("Coupe", 200, 3),
+      new Car("Wagon", 100, 5),
+      new Car("Limousine", 150, 4),
+      new ElectricCar("Electric Hatchback", 148, 5, 40)
+    };
+    PrintVehicles(cars);
+    
+    Comparison<Vehicle> comparisonFunction = (a, b) => -a.HorsePower.CompareTo(b.HorsePower);
+    IComparer<Vehicle> comparer = Comparer<Vehicle>.Create(comparisonFunction);
+
+    PrintBetterCar(cars[2], cars[3], comparer);
+    PrintBetterCar(cars.Skip(2).First(), cars.Last(), comparisonFunction);
+
+    PrintBetterCar(cars[2], cars[3], (a, b) => b.Doors - a.Doors);
+  }
+
+  static void PrintVehicles(IEnumerable<Vehicle> vehicles)
+  {
+    foreach (var vehicle in vehicles)
+    {
+      Console.WriteLine("\t " + vehicle.Model);
+    }
+  }
+
+  static void PrintBetterCar(Car a, Car b, IComparer<Car> comparer)
+  {
+    int result = comparer.Compare(a, b);
+    string betterModel = result <= 0 ? a.Model : b.Model;
+    string worseModel = result <= 0 ? b.Model : a.Model;
+    Console.WriteLine($"\t{betterModel} is better or equal than {worseModel}");
+  }
+
+  static void PrintBetterCar(Car a, Car b, Comparison<Car> comparer)
+  {
+    int result = comparer(a, b);
+    string betterModel = result <= 0 ? a.Model : b.Model;
+    string worseModel = result <= 0 ? b.Model : a.Model;
+    Console.WriteLine($"\t{betterModel} is better or equal than {worseModel}");
+  }
+}