c++ - 枚举类型中 const 说明符的作用是什么？

Question

enum foo : const unsigned int
{
    F,
    S,
    T
};

void func()
{
    foo p;
    p = F;
}

上面的编译所以底层类型不是 const 类型？

Answer 1

const 限定符在 enum-base 的规范中被忽略;它只是期望将整数类型用作枚举类型的基础类型，指定 const(或 volatile)没有多大意义。

(强调我的)

colon (:), followed by a type-specifier-seq that names an integral type (if it is cv-qualified, qualifications are ignored) that will serve as the fixed underlying type for this enumeration type

根据标准，[dcl.enum]/2 :

(强调我的)

The type-specifier-seq of an enum-base shall name an integral type; any cv-qualification is ignored.