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(newbie question) Covariance and contravarianceFirstly I don't have any theoretical background in Category Theory. My goal is just trying to understand the following: On wikipedia, A covariant type operator in a type system preserves the ordering ≤ of types. A contravariant operator reverses ≤. If neither of these apply, the operator is invariant. These terms come from category theory. What is type operator referring to in the context say Java ? The array type is usually covariant on the base type. Would I be right to say that the type operator is the assignment operator ? String[] a = new String[1]; Object[] b = a; Thanks. By chihiro at 20080107 03:16  LtU Forum  previous forum topic  next forum topic  other blogs  6048 reads

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