Generics: Why can't the compiler infer the type arguments in this case?

Question

I wanted to write an extension-method that would work on dictionaries whose values were some sort of sequence. Unfortunately, the compiler can\'t seem to infer the generic a

Answer 1

Why not leave out the type of the IEnumerable?

public static void SomeMethod
(this IDictionary dict)
where TValue : IEnumerable { }