Can traits be used on enum types? Yes. In fact, you already have multiple traits defined for your enum; the traits Debug, Copy and Clone: #[derive(Debug, Copy, Clone)] pub enum SceneType The problem is that you aren’t attempting to implement Playable for your enum, you are trying to implement it for one of the enum’s … Read more
Using GetHashCode() is incorrect. You should cast to int. Using it the way you do is asking for raptors(or Raymond) to come and eat you. That GetHashCode() happens to return the integer value of the enum is an implementation detail and may change in future versions of .net. GetHashCode() guarantees that if two values are … Read more
Yes. Java doesn’t have mechanism which lets us create unmodifiable array. So if values() would return same mutable array, we risk that someone could change its content for everyone. So until unmodifiable arrays will be introduced to Java, for safety values() must return new/separate array holding all values. We can test it with == operator: … Read more
Well this is a strange case. It appears that the problem is: In this case, the private member should be accessible (6.6.1.): Otherwise, the member or constructor is declared private, and access is permitted if and only if it occurs within the body of the top level class that encloses the declaration of the member … Read more
You can’t put a space in the middle of an identifier. Doing so ends that identifier and the parser assumes whatever comes next is a valid token in that statement’s context. There are few (if any) places that would be legal. Conventional Java value names would be: INDIA, // Or India, RUSSIA, // Russia, NORTH_AMERICA; … Read more
Drink.COFFEE.getGroupName(); Drink.COFFEE.COLUMBIAN.getLabel(); First off, that sample code you gave violates the “law of demeter” somewhat – as the COLUMBIAN instance field is only used to retrieve the label. Also, with that structure, COLUMBIAN has to be an instance of the COFFEE enum, but I don’t think that’s what you’re really going for here. someMethod(Drink type) … Read more
I had a similar question here, and my end result was to create a generic IValueConverter that passed the enum value I wanted to match in as the ConverterParameter, and it returns true or false depending on if the bound value matches the (int) value of the Enum. The end result looks like this: XAML … Read more
Starting from R2010b, MATLAB supports enumerations. Example from the documentation: classdef Colors properties R = 0; G = 0; B = 0; end methods function c = Colors(r, g, b) c.R = r; c.G = g; c.B = b; end end enumeration Red (1, 0, 0) Green (0, 1, 0) Blue (0, 0, 1) end … Read more
use this if (userProfile.AccountType == AccountType.Retailer) { … } If you want to get int from your AccountType enum and compare it (don’t know why) do this: if((int)userProfile.AccountType == 1) { … } Objet reference not set to an instance of an object exception is because your userProfile is null and you are getting property … Read more
<< is the bitshift operator. So 1 << 2 tells it to shift the bit two spaces over. Example: In binary the number 1 is: 0001 1 << 2 means to shift all the bits to the left 2 spaces, which results in this value: 0100 or 4. So the values of each ENUM in … Read more