// https://cirosantilli.com/linux-kernel-module-cheat#cpp-compile-time-magic

#if __cplusplus >= 201703L

#include <cassert>

#include <type_traits>

template<typename T>

struct MyClass {

MyClass() : myVar{0} {}

void modifyIfNotConst() {

if constexpr(!isconst) {

myVar = 1;

}

}

T myVar;

static constexpr bool isconst = std::is_const<T>::value;

};

#endif

int main() {

#if __cplusplus >= 201703L

MyClass<double> x;

MyClass<const double> y;

x.modifyIfNotConst();

y.modifyIfNotConst();

assert(x.myVar == 1);

assert(y.myVar == 0);

#endif

}