• Salih Dincer (46/67) Dec 04 2022 Hi All, are these results normal?

Salih Dincer <salihdb hotmail.com> writes:

Hi All, are these results normal?

The results have nothing to do with extern(c). I just wanted to 
see the simplest results.

```d
extern (C) void main()
{
   enum SAYI : char { bir = 49, iki }
   enum NUMS : SAYI {
         one = SAYI.bir,
         two = SAYI.iki
   }
   import core.stdc.stdio;

   printf("%c\n", SAYI.bir);     // okay, ASCII: 1
   printf("%c\n", NUMS.iki);     // okay, ASCII: 2

   printf("%c\n", NUMS.one.iki); // opps: ASCII: 2
   printf("%c\n", NUMS.two.iki); // opps: ASCII: 2

   // printf("%c\n", NUMS.three); // okay: ERROR

   printf("%c\n", NUMS.iki);     // opps: ASCII: 2
   printf("%c\n", NUMS.iki.iki); // opps: ASCII: 2

   enum Bar : SAYI { one }

   printf("[%c]\n", Bar.one);    // okay, ASCII: []
   assert(Bar.one == '\0');

   /* other error; Comparison between different enumeration types 
`Foo` and `SAYI`; If this behavior is intended consider using 
`std.conv.asOriginalType`
   enum Foo : SAYI { one, two }
   with (SAYI) enum Zoo : SAYI
   {
     one = bir, two
   }
   //*/
   with(SAYI)
   {
     enum Zoo : SAYI
     {
       one = bir,
       two = iki,
       three = cast(SAYI)'3'
     }
     printf("%c\n", Zoo.three); // okay, ASCII: 3
   }
}
```

[v2.099.0 Specification on the 
subject:](https://docarchives.dlang.io/v2.099.0/spec/enum.html)

 7. If there is no AssignExpression and it is not the first 
 EnumMember, it is given the value of the previous EnumMember+1. 
 If the value of the previous EnumMember is EnumBaseType.max, it 
 is an error. If the value of the previous EnumMember+1 is the 
 same as the value of the previous EnumMember, it is an error. 
 (This can happen with floating point types.)

 8. All EnumMembers are in scope for the AssignExpressions.
 ```d
 enum C
 {
    A = B,  // A = 4
    B = D,  // B = 4
    C = 3,  // C = 3
    D       // D = 4
 }
 enum E : C
 {
    E1 = C.D,
    E2      // error, C.D is C.max
 }
 ```

SDB 79