C++ check if statement can be evaluated constexpr

Question

Is there a method to decide whether something can be constexpr evaluated, and use the result as a constexpr boolean? My simplified use case is as follows:

te         


        

Answer 1

template struct require_constant;
template
concept has_constexpr_data = requires { typename require_constant; };

This is basically what's used by std::ranges::split_view.