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Enums in JavaScript?

What is the preferred syntax for defining enums in JavaScript? Something like:

my.namespace.ColorEnum = {
    RED : 0,
    GREEN : 1,
    BLUE : 2
}

// later on

if(currentColor == my.namespace.ColorEnum.RED) {
   // whatever
}

Or is there a more preferable idiom?

How can I represent an 'Enum' in Python?

I'm mainly a C# developer, but I'm currently working on a project in Python.

How can I represent the equivalent of an Enum in Python?

What does the [Flags] Enum Attribute mean in C#?

From time to time I see an enum like the following:

[Flags]
public enum Options 
{
    None    = 0,
    Option1 = 1,
    Option2 = 2,
    Option3 = 4,
    Option4 = 8
}

I don't understand what exactly the [Flags]-attribute does.

Anyone have a good explanation or example they could post?

Can you loop through all enum values? [duplicate]

This question already has an answer here:
How to enumerate an enum? 14 answers

public enum Foos
{
    A,
    B,
    C
}

Is there a way to loop through the possible values of Foos?

Basically?

foreach(Foo in Foos)

How to model type-safe enum types?

Scala doesn't have type-safe enums like Java has. Given a set of related constants, what would be the best way in Scala to represent those constants?

Best way to create enum of strings?

What is the best way to have a enum type represent a set of strings?

I tried this:

enum Strings{
   STRING_ONE("ONE"), STRING_TWO("TWO")
}

How can use them as Strings?

What is a typedef enum in Objective-C?

I don't think I fundamentally understand what an enum is, and when to use it.

For example:

typedef enum {
    kCircle,
    kRectangle,
    kOblateSpheroid
} ShapeType;

What is really being declared here?

Get int value from enum

I have a class called Questions (plural). In this class there is an enum called Question (singular) which looks like this.

public enum Question
{
    Role = 2,
    ProjectFunding = 3,
    TotalEmployee = 4,
    NumberOfServers = 5,
    TopBusinessConcern = 6
}

In the Questions class I have a get(int foo) function that returns a Questions object for that foo. Is there an easy way to get the integer value off the enum so I can do something like this Questions.Get(Question.Role)?

How do I enumerate an enum?

How can you enumerate an enum in C#?

E.g. the following code does not compile:

public enum Suit {
    Spades,
    Hearts,
    Clubs,
    Diamonds
}

public void EnumerateAllSuitsDemoMethod() {
    foreach (Suit suit in Suit) {
        DoSomething(suit);
    }
}

And gives the compile time error:

'Suit' is a 'type' but is used like a 'variable'

It fails on the Suit keyword, the second one.

Cast int to enum in C#

How can an int be cast to an enum in C#?

Convert a String to an enum in Java

Say I have an enum which is just

public enum Blah {
    A, B, C, D
}

and I would like to find the enum value of a string, for example "A" which would be Blah.A. How would it be possible to do this?

Is the Enum.valueOf() the method I need? If so, how would I use this?

How do I convert a string to an enum in C#?

What's the best way to convert a string to an enumeration value in C#?

I have an HTML select tag containing the values of an enumeration. When the page is posted, I want to pick up the value (which will be in the form of a string) and convert it to the enumeration value.

In an ideal world, I could do something like this:

StatusEnum MyStatus = StatusEnum.Parse("Active");

but that isn't valid code.

How to get C# Enum description from value? [duplicate]

Possible Duplicate:
Getting attributes of Enum’s value

I have an enum with Description attributes like this:

public enum MyEnum
{
    Name1 = 1,
    [Description("Here is another")]
    HereIsAnother = 2,
    [Description("Last one")]
    LastOne = 3
}

I found this bit of code for retrieving the description based on an Enum

public static string GetEnumDescription(Enum value)
{
    FieldInfo fi = value.GetType().GetField(value.ToString());

    DescriptionAttribute[] attributes =
        (DescriptionAttribute[])fi.GetCustomAttributes(
        typeof(DescriptionAttribute),
        false);

    if (attributes != null &&
        attributes.Length > 0)
        return attributes[0].Description;
    else
        return value.ToString();
}

This allows me to write code like:

var myEnumDescriptions = from MyEnum n in Enum.GetValues(typeof(MyEnum))
                         select new { ID = (int)n, Name = Enumerations.GetEnumDescription(n) };

What I want to do is if I know the enum value (e.g. 1) - how can I retrieve the description? In other words, how can I convert an integer into an "Enum value" to pass to my GetDescription method?

Forward declaring an enum in c++

I'm trying to do something like the following:

enum E;

void Foo(E e);

enum E {A, B, C};

which the compiler rejects. I've had a quick look on Google and the consensus seems to be "you can't do it", but I can't understand why. Can anyone explain? Many thanks.

Clarification 2: I'm doing this as I have private methods in a class that take said enum, and I do not want the enum's values exposed - so, for example, I do not want anyone to know that E is defined as

enum E {
    FUNCTIONALITY_NORMAL, FUNCTIONALITY_RESTRICTED, FUNCTIONALITY_FOR_PROJECT_X
}

as project X is not something I want my users to know about.

So, I wanted to forward declare the enum so I could put the private methods in the header file, declare the enum internally in the cpp, and distribute the built library file and header to people.

As for the compiler - it's GCC.

Most common C# bitwise operations on enums

For the life of me, I can't remember how to set, delete, toggle or test a bit in a bitfield. Either I'm unsure or I mix them up because I rarely need these. So a "bit-cheat-sheet" would be nice to have.

For example:

flags = flags | FlagsEnum.Bit4;  // Set bit 4.

or

if ((flags & FlagsEnum.Bit4)) == FlagsEnum.Bit4) // Is there a less verbose way?

Can you give examples of all the other common operations, preferably in C# syntax using a [Flags] enum?