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digitalmars.D - Re: Private enum members

reply Kagamin <spam here.lot> writes:
Justin Johansson Wrote:


 enum Color {
   private UNINITIALIZED = -1,
   RED, GREEN, BLUE
 }



It's syntactical ambiguity, I think. There's no much difference between
private UNINITIALIZED = -1,
RED, GREEN, BLUE

and

private UNINITIALIZED = -1, RED, GREEN, BLUE
Oct 26 2009
parent reply d-noob <doesnt exist.com> writes:
Kagamin Wrote:


 Justin Johansson Wrote:
 

 enum Color {
   private UNINITIALIZED = -1,
   RED, GREEN, BLUE
 }



 It's syntactical ambiguity, I think. There's no much difference between
 private UNINITIALIZED = -1,
 RED, GREEN, BLUE
 
 and
 
 private UNINITIALIZED = -1, RED, GREEN, BLUE



So let's fix it:

enum C {
  private:
  UNINITIALIZED = -1;
  public:
  RED, GREEN, BLUE;
}

But even now it's easy to set illegal values in client code:

C c = RED;
c--; // bang!

Gotta love the implicit conversions - this is almost like pointer arithmetics
Oct 26 2009
parent Kagamin <spam here.lot> writes:
d-noob Wrote:


 So let's fix it:
 
 enum C {
   private:
   UNINITIALIZED = -1;
   public:
   RED, GREEN, BLUE;
 }



See enums with virtual methods
http://java.sun.com/j2se/1.5.0/docs/guide/language/enums.html
Oct 26 2009