typeof(int) a; /* Specifies variable a which is of the type int */ 1. typeof('b') a; /* The same. typeof argument is an expression consisting of 1. character constant which has the type int */ 1. 以下示例用于声明指针和数组。为了进行对比,还给出了不带typeof的等效声明。 typeof(...
extern int foo();typeof(foo()) var; 使用typeof的声明限制 请注意,typeof构造中的类型名不能包括存储类说明符,如extern或static。只是同意包括类型限定符,如const或volatile。比如,下列代码是无效的,由于它在typeof构造中声明了extern: typeof(extern int) a; 下列代码使用外部链接来声明标识符b是有效的,表示...
这类似于sizeof关键字接受的操作数(与sizeof不同的是,位字段允许作为typeof实参,并被解释为相应的整数类型)。从语义上看,typeof关键字将用做类型名(typedef名称)并指定类型。 使用 下面是两个等效声明,用于声明int类型的变量a。 typeof(int) a; /* Specifies variable a which is of the type int */ ...
name(); if (std::is_const<TR>::value) r += " const"; if (std::is_volatile<TR>::value) r += " volatile"; if (std::is_lvalue_reference<T>::value) r += "&"; else if (std::is_rvalue_reference<T>::value) r += "&&"; return r; } The Results With this solution I...
aligned_storage_t aligned_union_t\ common_type_t conditional_t decay_t enable_if_t invoke_result_t make_signed_t make_unsigned_t remove_all_extents_t\ remove_const_t remove_cv_t remove_extent_t remove_pointer_t remove_reference_t remove_volatile_t result_of_t underlying_type_t\Classes...
h> int main(void) { clock_t t = clock(); double d; for (int n=0; n<10000; ++n) for (int m=0; m<10000; ++m) d += d*n*m; // reads and writes to a non-volatile printf("Modified a non-volatile variable 100m times. " "Time used: %.2f seconds\n", (double)(clock...
C++11 update to a very old question: Print variable type in C++. The accepted (and good) answer is to use typeid(a).name(), where a is a variable name. Now in C++11 we have decltype(x), which can turn an expression into a type. And decltype() comes with its own set of very...
A type qualifier cannot apply to user-defined types, but only to objects created from a user-defined type. Therefore, the following declaration is illegal: volatile struct omega { int limit; char code; }; However, if a variable or variables are declared within the same definition of the typ...
The compiler assumes that, at any point in the program, avolatilevariable can be accessed by an unknown process that uses or modifies its value. Regardless of the optimizations specified on the command line, the code for each assignment to or reference of avolatilevariable must be generated eve...
}/* Nothing is actually declared to be a PyObject, but every pointer to * a Python object can be cast to a PyObject*. This is inheritance built * by hand. Similarly every pointer to a variable-size Python object can, * in addition, be cast to PyVarObject*. */typedefstruct_object{...