47 lines
535 B
C#
47 lines
535 B
C#
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using System;
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struct S
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{
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public int ID { get; set; }
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}
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class C
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{
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public readonly int ID;
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private C (int id)
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{
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ID = id;
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}
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public static explicit operator C (S x)
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{
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throw new ApplicationException ("wrong conversion");
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}
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public static explicit operator C (S? x)
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{
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return new C (x.HasValue ? x.Value.ID : 5);
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}
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}
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public class Test
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{
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public static int Main ()
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{
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S? s = null;
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C c = (C) s;
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if (c.ID != 5)
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return 1;
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s = new S () { ID = 10 };
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c = (C) s;
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if (c.ID != 10)
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return 2;
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return 0;
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}
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}
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