mcs/tests/test-null-operator-08.cs

   1 using System;
   2
   3 interface I
   4 {
   5         void Foo (bool expected);
   6 }
   7
   8 struct S : I
   9 {
  10         bool flag;
  11
  12         public void Foo (bool expected)
  13         {
  14                 Console.WriteLine (flag);
  15                 if (expected != flag)
  16                         throw new ApplicationException ();
  17
  18                 flag = true;
  19         }
  20 }
  21
  22 class Program
  23 {
  24         static void M<T> (T x)
  25         {
  26                 object s = x?.ToString ();
  27                 System.Console.WriteLine (s);
  28
  29                 var h = x?.GetHashCode ();
  30                 System.Console.WriteLine (h);
  31         }
  32
  33         static void M2<T> (T[] x)
  34         {
  35                 object s = x?.ToString ();
  36                 System.Console.WriteLine (s);
  37
  38                 var h = x?.GetHashCode ();
  39                 System.Console.WriteLine (h);
  40         }
  41
  42         static void M2_2<T> (T[] x)
  43         {
  44                 object s = x[0]?.ToString ();
  45                 System.Console.WriteLine (s);
  46
  47                 var h = x[0]?.GetHashCode ();
  48                 System.Console.WriteLine (h);
  49         }
  50
  51         static void M3<T> (T? x) where T : struct
  52         {
  53                 object s = x?.ToString ();
  54                 System.Console.WriteLine (s);
  55
  56                 var h = x?.GetHashCode ();
  57                 System.Console.WriteLine (h);
  58         }
  59
  60         static void TestAddress_1<T> (T t) where T : I
  61         {
  62                 t?.Foo (false);
  63                 t?.Foo (true);
  64         }
  65
  66         static void TestAddress_2<T> (T[] t) where T : I
  67         {
  68                 t[0]?.Foo (false);
  69                 t[0]?.Foo (true);
  70         }
  71
  72         static void Main()
  73         {
  74                 M<string> (null);
  75                 M (1);
  76                 M("X");
  77
  78                 M2<int> (null);
  79                 M2<string> (null);
  80                 M2 (new [] { 1 });
  81                 M2 (new [] { "x" });
  82
  83                 M2_2 (new string [1]);
  84                 M2_2 (new int [1]);
  85
  86                 M3<int> (1);
  87                 M3<byte> (null);
  88
  89                 TestAddress_1 (new S ());
  90                 var ar = new [] { new S () };
  91                 TestAddress_2 (ar);
  92         }
  93 }