69 lines
853 B
C#
69 lines
853 B
C#
using System;
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public abstract class A<T>
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{
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public abstract G Foo<G> () where G : T;
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public virtual G Foo2<G> () where G : T
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{
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return default (G);
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}
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}
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public class B : A<int?>
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{
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public override G Foo<G> ()
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{
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return new G ();
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}
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public override G Foo2<G> ()
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{
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return base.Foo2<G> ();
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}
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}
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abstract class A2<T>
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{
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public abstract void Foo<U> () where U : struct, T;
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}
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class B2 : A2<System.ValueType>
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{
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public override void Foo<Y> ()
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{
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}
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}
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abstract class A3<T>
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{
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public abstract void Foo<U> () where U : class, T;
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}
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class B3 : A3<System.Object>
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{
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public override void Foo<Y> ()
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{
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}
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}
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class Program
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{
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public static int Main ()
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{
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var b = new B ();
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if (b.Foo<int?> () == null)
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return 0;
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b.Foo2<int?> ();
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var b2 = new B2 ();
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b2.Foo<byte> ();
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var b3 = new B3 ();
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b3.Foo<string> ();
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return 1;
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}
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}
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