typedef NS_ENUM(NSUInteger, SomeEnum) {
  SomeEnumNever = 0,
  SomeEnumSometimes = 1,
  SomeEnumAlways = 2,
};

static NSString *EnumToString(SomeEnum enum) {
  switch (enum) {
    case SomeEnumNever:
      return @"Never";
    case SomeEnumSometimes:
      return @"Sometimes";
    case SomeEnumAlways:
      return @"Always"
  }
}

NSString *enum = EnumToString(3);