C# Generic - Any way to declare T has an attribute?

[MyCustomClassAttribute]
public class Foo
{
}


public class Bar<T>
    where T : ??
{
    public T FooInstance;
}

I'm pretty sure this is impossible, but just thought I'd check. Any way to mak开发者_C百科e it so that T has to have a [MyCustomClassAttribute] on it?

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I am afraid this is impossible. Here's a list of all the possible generic constraints you could use.