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The Null Values article in the F# Language Reference show an example that uses it, but it does not explain what it does exactly. You can use the following code to check if an arbitrary value is ...
Question
f#
#1: Initial revision
by
toraritte
·
2024-01-05T15:57:18Z (12 months ago)
What does F#'s `box` keyword do and where is it documented?
The [Null Values][1] article in the [F# Language Reference][2] show an example that uses it, but it does not explain what it does exactly. > You can use the following code to check if an arbitrary value is > `null`. > > match box value with > | null -> printf "The value is null." > | _ -> printf "The value is not null." I went through the entire [PDF version][3] of the language reference, but there is not trace of it ever being introduced. [1]: https://learn.microsoft.com/en-us/dotnet/fsharp/language-reference/values/null-values [2]: https://docs.microsoft.com/dotnet/fsharp/language-reference/ [3]: https://learn.microsoft.com/pdf?url=https%3A%2F%2Flearn.microsoft.com%2Fen-us%2Fdotnet%2Ffsharp%2Ftoc.json