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Questions tagged [enums]

A data type consisting of a set of named values called elements, members or enumerators of the type.

This tag is for questions related to enumeration, enumerated-types (or enums) as related to programming.

In computer programming, an enumerated type (also called enumeration or enum) is a data type consisting of a set of named values called elements, members or enumerators of the type. The enumerator names are usually identifiers that behave as constants in the language. A variable that has been declared as having an enumerated type can be assigned any of the enumerators as a value.

From the wikipedia article on enumerated type

Rust and Swift

Unlike the other languages that take inspiration from , the enums in and are sum types (see, for example, sum types in Haskell):

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How to delete an enum type value in postgres?

How do I delete an enum type value that I created in postgresql? create type admin_level1 as enum('classifier', 'moderator', 'god'); E.g. I want to remove moderator from the list. I can't seem to find anything on the docs. I'm using Postgresql…
Amjith
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Enums in Javascript with ES6

I'm rebuilding an old Java project in Javascript, and realized that there's no good way to do enums in JS. The best I can come up with is: const Colors = { RED: Symbol("red"), BLUE: Symbol("blue"), GREEN:…
cypherfunc
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Convert Enum to String

Which is the preferred way to convert an Enum to a String in .NET 3.5? Enum.GetName Enum.Format ToString Why should I prefer one of these over the others? Does one perform better?
Eric Weilnau
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SQL query to get all values a enum can have

Postgresql got enum support some time ago. CREATE TYPE myenum AS ENUM ( 'value1', 'value2', ); How do I get all values specified in the enum with a query?
Wienczny
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C# vs Java Enum (for those new to C#)

I've been programming in Java for a while and just got thrown onto a project that's written entirely in C#. I'm trying to come up to speed in C#, and noticed enums used in several places in my new project, but at first glance, C#'s enums seem to be…
Ogre Psalm33
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Dart How to get the name of an enum as a String

Before enums were available in Dart I wrote some cumbersome and hard to maintain code to simulate enums and now want to simplify it. I need to get the name of the enum as a string such as can be done with Java but cannot. For instance little test…
Nate Lockwood
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Can my enums have friendly names?

I have the following enum public enum myEnum { ThisNameWorks, This Name doesn't work Neither.does.this; } Is it not possible to have enums with "friendly names"?
JL.
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Java enum - why use toString instead of name

If you look in the enum api at the method name() it says that: Returns the name of this enum constant, exactly as declared in its enum declaration. Most programmers should use the toString method in preference to this one, as…
spauny
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Can I set enum start value in Java?

I use the enum to make a few constants: enum ids {OPEN, CLOSE}; the OPEN value is zero, but I want it as 100. Is it possible?
qrtt1
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Swift: Convert enum value to String?

Given the following enum: enum Audience { case Public case Friends case Private } How do I get the string "Public" from the audience constant below? let audience = Audience.Public
ma11hew28
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What is the difference between `Enum.name()` and `Enum.toString()`?

After reading the documentation of String java.lang.Enum.name() I am not sure I understand when to use name() and when to use toString(). Returns the name of this enum constant, exactly as declared in its enum declaration. Most programmers should…
Micha Wiedenmann
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How can I lookup a Java enum from its String value?

I would like to lookup an enum from its string value (or possibly any other value). I've tried the following code but it doesn't allow static in initialisers. Is there a simple way? public enum Verbosity { BRIEF, NORMAL, FULL; private…
peter.murray.rust
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Should enums in C# have their own file?

I have a class which uses an enumeration, the enum is currently in its own file which seems wasteful. What is the general opinion on enums being placed within the namespace of a file that they are consumed in? Or should the enum really live in its…
Finglas
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Where is the documentation for the values() method of Enum?

I declare an enum as : enum Sex {MALE,FEMALE}; And then, iterate enum as shown below : for(Sex v : Sex.values()){ System.out.println(" values :"+ v); } I checked the Java API but can't find the values() method? I'm curious as to where this…
rai.skumar
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Typescript has unions, so are enums redundant?

Ever since TypeScript introduced unions types, I wonder if there is any reason to declare an enum type. Consider the following enum type declaration: enum X { A, B, C } var x: X = X.A; and a similar union type declaration: type X: "A" | "B" |…
prmph
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