syntax « enum « C Q&A

1. Is the last comma in C enum required?    stackoverflow.com

Is the last comma required in a C enum declaration? i.e. is the comma after VAL3 required?

enum{Val1, Val2, Val3,} someEnum;

Are there any side-effects of leaving it in/out Thanks

2. What is the return type of enum |?    stackoverflow.com

enum FileOpenFlags
{
    FileOpenFlags_Create = 1,
    FileOpenFlags_Truncate = 2,
};


FileOpenFlags flags = FileOpenFlags_Create | FileOpenFlags_Truncate;

Is it true the return type of enum | is also enum??

3. Syntax error in C    stackoverflow.com

 5 enum state {ST_BEFORE_KEY, ST_IN_KEY, ST_BEFORE_VALUE, ST_TERM, ST_ERR};
  6 
  7 typedef struct {
  8   state st;
      ...

The above code ...