Question

The standard way of declaring an enum in C++ seems to be:

enum <identifier> { <list_of_elements> };

However, I have already seen some declarations like:

typedef enum { <list_of_elements> } <identifier>;

What is the difference between them, if it exists? Which one is correct?

Answer 1

C compatability.

In C, union, struct and enum types have to be used with the appropriate keyword before them:

enum x { ... };

enum x var;

In C++, this is not necessary:

enum x { ... };

x var;

So in C, lazy programmers often use typedef to avoid repeating themselves:

typedef enum x { ... } x;

x var;