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Enumerations

Enumerations – usually called just enums – are a way of defining groups of related values in a way that makes them easier to use.

For example, if you wanted to write some code to represent the success or failure of some work you were doing, you could represent that as strings:

let result = "failure"

But what happens if someone accidentally uses different naming?

let result2 = "failed"
let result3 = "fail"

All those three are different strings, so they mean different things.

With enums we can define a Result type that can be either success or failure, like this:

enum Result {
    case success
    case failure
}

And now when we use it we must choose one of those two values:

let result4 = Result.failure

This stops you from accidentally using different strings each time.

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