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POAmbiguous Invocation on Generic ContinueWith
 

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    <p>I'm writing a simple C# console application that uses Asynchronous Tasks and Entity Framework (with the intent to run it under Linux (RHEL) with Mono, but that's a whole other challenge). Note that I'm targeting .NET 4.0, so I'm using <code>.ContinueWith()</code> instead of <code>await</code>.</p> <p>This, plus the EF DB model of a Northwind Database, is the entirety of the application:</p> <pre class="lang-cs prettyprint-override"><code>using System; using System.Linq; using System.Threading.Tasks; namespace MonoEF { class Program { private static Model.NorthwindEntities _db = new Model.NorthwindEntities(); static void Main(string[] args) { try { GetCustomerNamesAsync().ContinueWith(t =&gt; { if (t.IsFaulted) Console.WriteLine(t.Exception.Flatten.ToString); else if (t.IsCompleted) foreach (string result in t.Result) Console.WriteLine(result); }); Console.ReadLine(); } catch (Exception ex) { Console.WriteLine(ex.ToString()); } } private static Task&lt;string[]&gt; GetCustomerNamesAsync() { return Task.Factory.StartNew(() =&gt; (from c in _db.Customers select c.ContactName).Distinct().ToArray()); } } } </code></pre> <p>The problem is I'm getting the following error at the <code>.ContinueWith()</code>:</p> <pre><code>Ambiguous Invocation: System.Threading.Tasks.Task.ContinueWith(System.Action&lt;System.Threading.Tasks.Task&lt;string[]&gt;&gt;) (in class Task&lt;string[]&gt;) System.Threading.Tasks.Task.ContinueWith(System.Action&lt;System.Threading.Tasks.Task&gt;) (in class Task) match </code></pre> <p>To me, the invocation shouldn't be ambiguous, the compiler should prefer the generic Task over the non-generic Task, especially as it's the output of <code>GetCustomerNamesAsync()</code>. However, as a VB.NET developer, I'm probably relying on <code>Option Infer</code> in this situation.</p> <p>How would I go about explicitly letting the compiler know which invocation I want it to use in C#?</p>
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