C++ typedef enum and just enum [duplicate]

Question

What exactly is the difference between:

typedef enum {
  something1,
  something2,
  .....
  somethingN
} myEnum;

end just

enum myEnum{
  something1,
  something2,
  .....
  somethingN
};

I know in first case I have typedefed unnamed enum, of course, just wonder which approach is better and why?

Answer 1

The first variant was useful in C, because otherwise you would have to write enum myEnum everywhere you wished to use it.

This is not the case in C++. So, AFAIK, there is no benefit to the first case in C++ (unless you're defining e.g. an interface that needs to be shared with C).

Answer 2

No difference. In fact, the first version is C-style coding.

C++11 has introduced stronly-typed enum, which you define as:

enum class myEnum  //note the 'class' keyword after the 'enum' keyword
{   
  something1,
  something2,
  .....
  somethingN
};

In C++03, enums are not type-safe, they're essentially integers, and can mix with other integral types implicitly, and another problem with them is that they don't have scope; you can use its member without qualifying its type; you can use something1. Whereas C++11 strongly-typed enums are type-safe, and they've scope; you've to use myEnum::something1.

Answer 3

I wouldn't use the first one. It is almost the same as the other one. In C++11, with the second you can write myEnum::something1 but not with the first one. Also in C++11, you can forward declare enums in some cases, but it is impossible to do forward declarations of unamed types and you can't forward declare typedefs either.