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Say I want to validate an input that has to satisfy one of a number of functions. What is the best way to do this in F#? Here’s a little example I came up with. 

let funcs = 
            [
                fun x -> x % 2 = 0
                fun x -> x % 3 = 0
                fun x -> x % 5 = 0
            ]

let oneWorks x = funcs |> List.tryFind (fun f -> f x = true) |> Option.isSome

oneWorks 2 //true
oneWorks 3 //true
oneWorks 5 //true
oneWorks 7 //false
Brett Rowberry
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    What you have is fine, apart from the `= true` bit, which is redundant. – kaefer Oct 18 '18 at 05:19
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    You could also simplify it by using [List.exists](https://msdn.microsoft.com/en-us/visualfsharpdocs/conceptual/list.exists%5B't%5D-function-%5Bfsharp%5D), then you'll avoid Option.isSome. – hlo Oct 18 '18 at 06:29

1 Answers1

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As the comments say, what you have will work fine.

However, I would simplify it to:

let any x = funcs |> Seq.exists (fun f -> f x)

any 2 //true
any 3 //true
any 5 //true
any 7 //false
goric
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