52 lines
791 B
C#
52 lines
791 B
C#
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using System;
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class TestA
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{
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public string value;
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public TestA (string value)
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{
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this.value = value;
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}
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public string Select<U> (Func<TestA, U> f)
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{
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return value;
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}
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}
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static class TestB
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{
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static public TestA Where(this TestA a, Func<TestA,bool> predicate)
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{
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if (predicate (a))
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return new TestA ("where used");
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return null;
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}
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}
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public class CustomQueryExpressionPattern
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{
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public static int Main ()
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{
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var v = new TestA ("Oh yes");
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string foo = from a in v select a;
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if (foo != "Oh yes")
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return 1;
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v = new TestA ("where?");
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// It also tests that select is not called in this case
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v = from a in v where a.value != "wrong" select a;
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if (v.value != "where used")
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return 1;
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Console.WriteLine (v.value.ToString ());
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return 0;
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}
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}
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