57 lines
1.0 KiB
Plaintext
57 lines
1.0 KiB
Plaintext
Once you modify a closure, any use of it could provide unexpected results.
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== Noncompliant Code Example
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----
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var x = 0;
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Func<int> f1 = () => x; // Noncompliant
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x = 1;
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Console.WriteLine(f1());
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var input = new[] { 1, 2, 3 };
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var fs = new List<Func<int>>();
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for (var i = 0; i < input.Length; i++) {
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Func<int> f = () => input[i]; // Noncompliant
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fs.Add(f);
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}
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Console.WriteLine(fs[0]()); //Access to modified closure yields Exception
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----
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== Compliant Solution
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----
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var x = 0;
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var xx = x;
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Func<int> f = () => xx;
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x = 1;
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Console.WriteLine(f());
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var input = new[] { 1, 2, 3 };
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var fs = new List<Func<int>>();
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for (var i = 0; i < input.Length; i++) {
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var ii = i;
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Func<int> f = () => input[ii];
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fs.Add(f);
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}
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Console.WriteLine(fs[0]());
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----
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or
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----
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var input = new[] { 1, 2, 3 };
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var fs = input.Select(t => (Func<int>) (() => t)).ToList();
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Console.WriteLine(fs[0]());
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----
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ifdef::env-github,rspecator-view[]
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'''
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== Comments And Links
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(visible only on this page)
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include::comments-and-links.adoc[]
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endif::env-github,rspecator-view[]
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