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166

answers:

1
+2  Q: 

How do I get the current sequence number in an iteration in F#?

Consider the following code to demonstrate the question:

let sequence = Seq.initInfinite (fun _ -> "Element")
Seq.iter (fun _ -> printf "Element no: ?") sequence

Is it in any way possible to get the current sequence number (e.g. its rank) to print?

+6  A: 

Use the iteri function:

let sequence = Seq.initInfinite (fun _ -> "Element")
sequence |> Seq.iteri (fun i _ -> printfn "Element no. %d" i)
cfern  2009-07-07 07:01:06

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