do while 宏定义如何使用?

#define verification(lhs,rhs,str) do { 
		if (lhs == rhs) { 
			std::cout << rang::style::bold << rang::fg::green << "[Success]" << rang::style::reset << " " << str << std::endl; 
		}else {	
			std::cout << rang::style::bold << rang::fg::red << "[Fail]" << rang::style::reset << "    " << str << std::endl; 
		} 
	} while (0)