55 lines
633 B
C#
55 lines
633 B
C#
using System;
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interface IFoo<T>
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{
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T Call ();
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}
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class C1
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{
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public void Foo<T> (IFoo<T> t) where T : class
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{
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t?.Call ();
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var x = t?.Call ();
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}
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public void Foo2<T> (IFoo<T> t)
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{
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t?.Call ();
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}
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}
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class C2<T> where T : class
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{
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C2<T> i;
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T field;
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public void Foo ()
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{
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var x = i?.field;
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}
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}
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class Program
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{
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static void Test<T>(Func<T> func) where T : struct
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{
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var r = func?.Invoke ();
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}
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static void Test2<T>(Func<T> func)
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{
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func?.Invoke ();
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}
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static void Main()
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{
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new C1 ().Foo<Program> (null);
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new C1 ().Foo2<Program> (null);
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new C2<string> ().Foo ();
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Test (() => 1);
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Test (() => 2);
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}
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} |