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POC# generic implicit cast on Interface failed
 

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    <p>Why will the below not compile? What's special about the interface that causes the compiler to think it can't cast from <code>Container&lt;T&gt;</code> to <code>T</code>, when <code>T</code> is an interface? I don't think its a covariant issue, as I'm not downcasting, but perhaps it is. This is quite like <a href="https://stackoverflow.com/questions/393701/why-c-compiler-doesnt-call-implicit-cast-operator">Why C# compiler doesn't call implicit cast operator?</a> but I don't think it's quite the same.</p> <pre><code>Product pIn =null; Product pOut; Container&lt;Product&gt; pContainer; List&lt;Product&gt; pListIn = null; List&lt;Product&gt; pListOut; Container&lt;List&lt;Product&gt;&gt; pListContainer; IList&lt;Product&gt; pIListIn = null; IList&lt;Product&gt; pIListOut; Container&lt;IList&lt;Product&gt;&gt; pIListContainer; pContainer = pIn; pOut = pContainer; // all good pListContainer = pListIn; pListOut = pListContainer; // all good too pIListContainer = pIListIn; // fails , cant do implicit cast for some reason pIListOut = pIListContainer; // and here too </code></pre> <hr> <pre><code>class Container&lt;T&gt; { private T value; private Container(T item) { value = item; } public static implicit operator Container&lt;T&gt;(T item) { return new Container&lt;T&gt;(item); } public static implicit operator T(Container&lt;T&gt; container) { return container.value; } } </code></pre> <hr> <pre><code>Cannot implicitly convert type 'Container&lt;IList&lt;Product&gt;&gt;' to 'IList&lt;Product&gt;'. An explicit conversion exists (are you missing a cast?) Cannot implicitly convert type 'IList&lt;Product&gt;' to 'Container&lt;IList&lt;Product&gt;&gt;'. An explicit conversion exists (are you missing a cast?) </code></pre>
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    2. CO+1 - Just found this compile error and wanted to ask this!
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