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    <p><em>Generics is used to re-use a behaviour that needs to be described beyond the type</em> - or at least within the restrictions enforced by the <code>where</code> clause.</p> <p>The example you have seen, IMHO, is a <strong>generics anti-pattern</strong>. Type should not matter or if it does, should only matter if it is defined in the restrictions - i.e. <code>where</code> clause.</p> <p>So basically, a generic abstract class which expects all subclasses to implement an abstract, is <strong>not using the genericness</strong>. I cannot just simply start using <code>Generic&lt;MyType&gt;</code> which is the point of generics.</p> <p>I believe that defeats the point. </p> <p>In this case there is a <strong>slight benefit</strong> in using a generic abstract class/interface and that is <strong>type safety</strong> achieve for <code>PerformSpecificTask</code>.</p> <hr> <h1>UPDATE</h1> <p>I knew it is a contentious issue and I would be fired at left and right, but I believe it is the case.</p> <p>A class can happily subclass a generic class and add more functionality. But in this case, it is the <strong>extra functionality that defines the identity of that class.</strong> When I cannot just say <code>Generic&lt;MyOwnTypeOfVolition&gt;</code> then I have defeated the objective of generics. Sometimes, however, it is not the generics which I am concerned with - it is the <strong>interface</strong> which seems to be the case here.</p> <hr> <h1>UPDATE 2</h1> <p>A classic example, is <code>IConvertible</code> in .NET Framework. </p> <p>You could setup a generic interface/abstract class for it and ask all subclasses to implement it, but the framework makes it an optional case and supports it only for classes implementing the interface.</p>
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    1. POIs there a name for this pattern of using generics?
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    1. COI have to say that I really am strongly against this type of thinking. The problem is not that one is allowed to do this in C#, it's rather that C# doesn't have a larger and more orthogonal system for generics. An abstract base class is underspecified in terms of behavior. I see no reason why it can't also be underspecified in terms of types, to be filled in by the derived classes.
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    2. COWhat, so implementing a non-generic collection by inheriting from [Collection<T>](http://msdn.microsoft.com/en-us/library/ms132397.aspx#inheritanceContinued) is an anit-pattern?
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    3. COSo if I have a CustomerPageController and a PersonPageController, which work with Customer and Person objects respectively, and I have a Repository behind the scenes that can handle either object generically but the validation would be totally different, then I can't expose a Save() method from a generic base while implementing my own type-specific Validate()?
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