Question

I have class Distance and typedef enum Unit,

@interface Distance:NSObject{

double m_miles;

}

@property double m_miles;

-(Distance *) initWithDistance: (double) value andUnit:(Unit) unit;

@implementation Distance

-(Distance *)initWithDistance: (double) value andUnit:(Unit) unit{

  self = [super init];

 if (self){

   switch (unit) {

     case Unit.miles:  m_miles = value;

                       break;

    case Unit.km:      m_miles = value/1.609344;

                       break;
}


}

Where do I declare my enum Unit? How to access

typedef enum{

    miles;

    km;

}Unit

In the other class I should be able to call Distance.Unit.km or miles:

Distance *a = [[Distance alloc] initWithDistance: 10.2 andUnit: Distance.Unit.km];

Answer 1

In C an enum doesn’t makes its values “qualified”. You have to access it with

Distance *a = [[Distance alloc] initWithDistance: 10.2 andUnit:km];
//                                                             ^^
//                                                             no Distance.Unit.stuff