F# – Define empty class, struct or interface types

In C#, you define an empty class, struct, or interface like this:

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So how do you define an empty type in F#?

Well, whenever you define a new class in F#, the compiler infers the class and end tokens at the beginning and end of the class’s definition, as you can see from below:

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So the easiest way to define an empty type is to specify the class and end tokens explicitly:

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Running these few lines of code into the F# interactive outputs the following:

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For class types, you also have other alternative techniques, such as:

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