事实上这个概念谁都有,只是三种声明方式非常相似很容易记混。
Bjarne在他的The C++ Programming Language里面给出过一个助记的方法:
把一个声明从右向左读。
char * const cp; ( * 读成 pointer to )
cp is a const pointer to char
const char * p;
p is a pointer to const char;
char const * p;
同上因为C++里面没有const*的运算符,所以const只能属于前面的类型。
C++标准规定,const关键字放在类型或变量名之前等价的。 const int n=5; //same as below
int const m=10; |
const int *p; //same as below const (int) * p
int const *q; // (int) const *p |
char ** p1;
// pointer to pointer to char
const char **p2;
// pointer to pointer to const char
char * const * p3;
// pointer to const pointer to char
const char * const * p4;
// pointer to const pointer to const char
char ** const p5;
// const pointer to pointer to char
const char ** const p6;
// const pointer to pointer to const char
char * const * const p7;
// const pointer to const pointer to char
const char * const * const p8;
// const pointer to const pointer to const char
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