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POMonodroid generics not covariant?
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copied!<p><strong>EDIT:</strong> <em>It seems to be confirmed that covariant generics are not yet supported. To make sure it makes it in the next release please email Xamarin and request this feature.</em></p> <p>The following code gives me an error (at the linq statement). Identical code works fine in Microsoft clr c# 4.0.</p> <p><strong>Error:</strong></p> <pre><code>Cannot implicitly convert type 'System.Collections.Generic.IEnumerable<LinqTest.Person>' to 'System.Collections.Generic.IEnumerable<LinqTest.Entity>'. An explicit conversion exists (are you missing a cast?) </code></pre> <p><strong>Code:</strong></p> <pre><code>[Activity(Label = "LinqTest", MainLauncher = true, Icon = "@drawable/icon")] public class Activity1 : Activity { protected override void OnCreate(Bundle bundle) { base.OnCreate(bundle); var names = new List<string> { "Joe", "Bob", "Jim", "Jane" }; IEnumerable<Entity> query = from e in names select new Person() {Name = e}; SetContentView(Resource.Layout.Main); var button = FindViewById<Button>(Resource.Id.MyButton); button.Click += delegate { button.Text = string.Format("{0}", query.Count()); }; } } public class Entity { public string Name { get; set; } } public class Person : Entity { public string Workplace { get; set; } } public class Animal : Entity { public string FurColour { get; set; } } </code></pre> <p>Am I correct or am I missing something? If so recommendations on refactoring this?</p> <p><strong>Also, if so, consider this an official feature request for monodroid - support for covariant generic support. :)</strong></p> <p>Thanks.</p>

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