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Calling a function with an array/list of parameters
f#

Hello,

in Python, if I have a function

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def myfun(a, b, c):
       return a + b + c

and have a list

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a = [2, 4, 6]

I can call the function myfun with "*a" which will unpack the values in the list use them as individual parameters

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print myfun(*a)

which would be the same as calling

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print myfun(2, 4, 6)

.

Is there any way to do this in F#? Say I have a list of parameters and a function taking the same number of parameters as present in the list - how would I go about to do that?

My first thought would be to recursively apply one parameter at the time, currying my way through the list. Is this a viable method?

Thanks,
Rickard

.

Is there any way to do this in F#? Say I have a list of parameters and a function taking the same number of parameters as present in the list - how would I go about to do that?

Well, you could use a match. Not as clean, but it does either safely unpack the list or handle if it is the wrong shape.

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let myfun a b c = a + b + c
let a = [ 1; 2; 3]
printfn "%i" (match a with [x;y;z] -> myfun x y z | _ -> failwith "Wrong shape")
By on 5/15/2009 7:53 AM ()

Thank you, that was very helpful!

By on 5/18/2009 11:37 PM ()

I don't think your suggested approach is viable (the types will not work out).

Overall I don't think there's any type-safe way to do this, so I think you'd have to invoke the method via reflection.

By on 5/14/2009 9:18 AM ()

Thank you. I have to find another way somehow.

By on 5/14/2009 11:08 AM ()

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