I've got an array of strings, call it a, where each individual string represents a number. I also have a function f : int -> int -> int, which I want to use to "reduce a to a single number". I would like to write:
a |> Array.reduce (fun x y -> f (int32 x) (int32 y))
but this does not work, because the type of "reduce" forbids me from returning integers from f (since a is an array of strings)
Is there a functional way to make this work without having to return a string from
for casting the string array to an int array beforehand?
Array.reduce mapping firstIf you don't want to adapt your f to handle strings, and you want to use Array.reduce then yeah I guess you should convert first (and to be honest: it seems easier than doing it manually with your wrapper-lambda) - so why not just use
a
|> Array.map int32
|> Array.reduce f
instead?
if you are concerned with the overhead of producing an intermediate Array you can always switch Array. with Seq. to to it lazily:
a |> Seq.map int32 |> Seq.reduce f
Array.foldaside from that you can always fold to your hearts desire:
a |> Array.fold (fun n s -> n + int32 s) 0
so you might call this more functional or not ;)
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