Primary templates do not have template argument lists; this list is implied in the template parameter list.
Template parameters specified in a primary template but not used in a partial specialization are omitted from the template parameter list of the partial specialization. The order of a partial specialization's argument list is the same as the order of the primary template's implied argument list.
In a template argument list of a partial template parameter, you cannot have an expression that involves non-type arguments unless that expression is only an identifier. In the following example, the compiler will not allow the first partial specialization, but will allow the second one:
template<int I, int J> class X { };
// Invalid partial specialization
template<int I> class X <I * 4, I + 3> { };
// Valid partial specialization
template <int I> class X <I, I> { }; The type of a non-type template argument cannot depend on a template parameter of a partial specialization. The compiler will not allow the following partial specialization:
template<class T, T i> class X { };
// Invalid partial specialization
template<class T> class X<T, 25> { };A partial specialization's template argument list cannot be the same as the list implied by the primary template.
You cannot have default values in the template parameter list of a partial specialization.
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