Nullable and Pattern Matching

Pattern Is

An is pattern checks a value's shape and creates a typed local variable.

Pattern Is

PatternIs.cs 
using System;

class Program
{
    static void Main()
    {
        object value = ;
        string result;

        if (value is int number)
        {
            result = "int:" + (number * 2);
        }
        else
        {
            result = "other:" + value;
        }

        Console.WriteLine($"result={result}");
    }
}

using System;

class Program
{
    static void Main()
    {
        object value = ;
        string result;

        if (value is int number)
        {
            result = "int:" + (number * 2);
        }
        else
        {
            result = "other:" + value;
        }

        Console.WriteLine($"result={result}");
    }
}

using System;

class Program
{
    static void Main()
    {
        object value = ;
        string result;

        if (value is int number)
        {
            result = "int:" + (number * 2);
        }
        else
        {
            result = "other:" + value;
        }

        Console.WriteLine($"result={result}");
    }
}
is pattern An `is` pattern checks a value and extracts a usable variable.