using System;

using City = NewType<string, CityDim>;
using Country = NewType<string, CountryDim>;

public struct CityDim {}
public struct  CountryDim {}
struct CountryInfo{};

public struct NewType<TIdentifier, TTag> : IComparable<NewType<TIdentifier, TTag>>, IEquatable<NewType<TIdentifier, TTag>>
    where TIdentifier : IComparable<TIdentifier>, IEquatable<TIdentifier>
{
    private TIdentifier _value;
    
    public NewType(TIdentifier value)
    {
        _value = value;
    }
    
    public TIdentifier Value
    {
        get { return _value; }
    }
    
    public override string ToString() 
    {
        return _value.ToString();
    }
        
    public override bool Equals(object obj)
    {
        if (obj is NewType<TIdentifier, TTag>)
        {
            var other = (NewType<TIdentifier, TTag>) obj;
            return Equals(other);
        }
        return false;
    }
        
    public override int GetHashCode()
    {
        return _value.GetHashCode();
    }
        
    public bool Equals(NewType<TIdentifier, TTag> other)
    {
        return _value.Equals(other.Value);
    }
        
    public int CompareTo(NewType<TIdentifier, TTag> other)
    {
        return _value.CompareTo(other.Value);
    }

    public static bool operator== (NewType<TIdentifier, TTag> id1, NewType<TIdentifier, TTag> id2)    
    {
        return id1.Equals(id2);
    }
        
    public static bool operator != (NewType<TIdentifier, TTag> id1, NewType<TIdentifier, TTag> id2)    
    {
        return !id1.Equals(id2);
    }
        
}

public class Program
{
    static CountryInfo? findCountry(Country c) {
        return null;
    }
    
    public static void Main()
    {
        var city = new City("Moskow");
        var country = new Country("Russia");

        findCountry(country); // ok
        //findCountry(city); // выдаст ошибку на этапе компиляции
        
        //Console.WriteLine("Are equals: {0}", city == country); // выдаст ошибку на этапе компиляции
        
        var city2 = new City("Moskow");
        Console.WriteLine("Are equals: {0}", city == city2);
    }
}