#include <iostream>
 
namespace Implementation
{
	using Preferred = int;
	using Fallback = char;
 
	template <std::size_t Size>
	void String(Preferred, const char (&string)[Size])
	{
		std::cout << "Constant string" << std::endl;
	}
 
	void String(Fallback, const char* string)
	{
		std::cout << "Non-constant string" << std::endl;
	}
}
 
template <typename T>
void String(const T& string)
{
	Implementation::String(0, string);
}
 
int main(int argc, char* argv[]) 
{
	String("Test"); // Detects constant string
	String(argv[0]); // Detects non-constant string
}

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