90 lines
1.2 KiB
C#
90 lines
1.2 KiB
C#
// Compiler options: -langversion:default
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//
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// Test for contravariance support in delegates
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//
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using System;
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public class A {
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protected string name;
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public A (string name)
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{
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this.name = "A::" + name;
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}
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public A ()
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{
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}
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public string Name {
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get {
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return name;
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}
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}
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}
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public class B : A {
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public B (string name)
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{
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this.name = "B::" + name;
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}
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public B ()
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{
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}
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}
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public class C : B {
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string value;
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public C (string name, string value)
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{
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this.name = "C::" + name;
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this.value = value;
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}
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public string Value {
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get {
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return value;
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}
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}
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}
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public class Tester {
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delegate string MethodHandler (C c);
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static string MethodSampleA (A value)
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{
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return value.Name;
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}
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static string MethodSampleB (B value)
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{
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return value.Name;
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}
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static string MethodSampleC (C value)
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{
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return value.Name + " " + value.Value;
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}
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public static void Main ()
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{
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MethodHandler da = MethodSampleA;
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MethodHandler db = MethodSampleB;
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MethodHandler dc = MethodSampleC;
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C a = new C ("Hello", "hello");
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C b = new C ("World", "world");
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C c = new C ("!", "!!!");
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Console.WriteLine (da (a));
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Console.WriteLine (db (b));
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Console.WriteLine (dc (c));
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}
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}
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