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An simple instructions on how to use enum in typescript

In TypeScript 1.8+, you can create a string literal type to define the type and an object with the same name for the list of values. It mimics a string enum's expected behaviour.

Here's an example:

type MyStringEnum = "member1" | "member2";

const MyStringEnum = {
    Member1: "member1" as MyStringEnum,
    Member2: "member2" as MyStringEnum
};

Which will work like a string enum:

// implicit typing example
let myVariable = MyStringEnum.Member1; // ok
myVariable = "member2";                // ok
myVariable = "some other value";       // error, desired

// explict typing example
let myExplicitlyTypedVariable: MyStringEnum;
myExplicitlyTypedVariable = MyStringEnum.Member1; // ok
myExplicitlyTypedVariable = "member2";            // ok
myExplicitlyTypedVariable = "some other value";   // error, desired

Make sure to type all the strings in the object! If you don't then in the first example above the variable would not be implicitly typed to MyStringEnum.

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