I have following simplified example code where I attempt to figure out whether given value is the maximum value of enum of it’s type.
enum class MyEnum : unsigned char {
VALUE,
OTHER_VALUE,
_LAST
};
template<typename T, T _L>
bool is_not_last(T value) {
return value < _L;
}
int main()
{
is_not_last<MyEnum, MyEnum::_LAST>(MyEnum::OTHER_VALUE);
return 0;
}
How can I format template so I can call is_not_last without specifying type first.
Desired outcome:
is_not_last<MyEnum::_LAST>(MyEnum::OTHER_VALUE);
Following declarations didn’t work:
template<T _L>
bool is_not_last(T value); // Doesn't have typename specified
template<typename T _L>
bool is_not_last(T value); // Invalid syntax
I feel like compiler should be able to deduce type from MyEnum::_LAST but I haven’t been able to figure that out.
Thank you very much.
>Solution :
Since C++17, you might do
template <auto L>
bool is_not_last(decltype(L) value) {
return value < L;
}