这两个声明之间有什么不同：

I am new in C programming and I wondered what is the difference between these two declarations:

我是C编程的新手,我想知道这两个声明之间有什么区别:

const int a;

and

int const a;

Both are well accepted by the compiler.

两者都被编译器很好地接受了。

3 个解决方案

#1

There is no difference. Both are same. int and const both are declaration specifiers and they can occur in any order. Grammar says all about it

没有区别。两者都是一样的。 int和const都是声明说明符,它们可以按任何顺序出现。语法说的都是关于它的

C11: 6.7 Declarations:

declaration-specifiers:

storage-class-specifier declaration-specifiers_opt
type-specifier declaration-specifiers_opt
type-qualifier declaration-specifiers_opt
function-specifier declaration-specifiers_opt
alignment-specifier declaration-specifiers_opt

storage-class-specifier declaration-specifiersopt type-specifier declaration-specifiersopt type-qualifier declaration-specifiersopt function-specifier declaration-specifiersopt alignment-specifier declaration-specifiersopt

C11: 6.7.2 Type specifiers (p2):

[...] the type specifiers may occur in any order, possibly intermixed with the other declaration specifiers.

[...]类型说明符可以按任何顺序出现,可能与其他声明说明符混合。

#2

No difference.

From Wikipedia:

For simple non-pointer data types, applying the const qualifier is straightforward. It can go on either side of the type for historical reasons (that is, const char foo = 'a'; is equivalent to char const foo = 'a';). On some implementations, using const on both sides of the type (for instance, const char const) generates a warning but not an error.

对于简单的非指针数据类型,应用const限定符很简单。由于历史原因,它可以在类型的任何一侧出现(即,const char foo ='a';等同于char const foo ='a';)。在某些实现中,在类型的两侧使用const(例如,const char const)会生成警告但不会生成错误。

#3

They are both same. You declared 2 constants variables.

它们都是一样的。你声明了2个常量变量。