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using namespace std;
 
template <typename IntType, IntType MIN_VAL, IntType MAX_VAL>
struct BoundInt
{
	static constexpr IntType MIN = MIN_VAL;
	static constexpr IntType MAX = MAX_VAL;
 
	IntType value;
};
 
template <typename T> struct ConversionTraits;
 
template <typename T>
struct Value
{
	// Pointless for the sake of this example
	void convert()
	{
		ConversionTraits<T>::convert();
	}
 
	T value;
};
 
// this 'implementation' is also pointless for example purposes
struct ConvertImpl
{
	static void convert() { }
};
template <> struct ConversionTraits<int> : public ConvertImpl {};
 
// This is my problem. How do I partially specialise for something that has
// constants as template parameters.
template <typename IntType>
struct ConversionTraits< BoundInt<IntType, IntType, IntType> >
{
	static void convert() {}
};
 
int main()
{
	Value<int> intval;
	intval.convert();
 
	Value<BoundInt<unsigned, 0, 100>> value;
	value.convert();
}
 

prog.cpp:36:60: error: type/value mismatch at argument 2 in template parameter list for ‘template<class IntType, IntType MIN_VAL, IntType MAX_VAL> struct BoundInt’
 struct ConversionTraits< BoundInt<IntType, IntType, IntType> >
                                                            ^
prog.cpp:36:60: error:   expected a constant of type ‘IntType’, got ‘IntType’
prog.cpp:36:60: error: type/value mismatch at argument 3 in template parameter list for ‘template<class IntType, IntType MIN_VAL, IntType MAX_VAL> struct BoundInt’
prog.cpp:36:60: error:   expected a constant of type ‘IntType’, got ‘IntType’
prog.cpp:36:62: error: template argument 1 is invalid
 struct ConversionTraits< BoundInt<IntType, IntType, IntType> >
                                                              ^
prog.cpp: In instantiation of ‘void Value<T>::convert() [with T = BoundInt<unsigned int, 0u, 100u>]’:
prog.cpp:47:16:   required from here
prog.cpp:20:32: error: incomplete type ‘ConversionTraits<BoundInt<unsigned int, 0u, 100u> >’ used in nested name specifier
   ConversionTraits<T>::convert();
                                ^

Standard output is empty