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Nested Array Length
f#

Hi

I'm trying to get the size of a nested array, but in first round, just the amount of elements in the outer array.
Now one would think arr.Length would do the trick, but it seems not!

#light
open System;

// Define our sets.
let sets = [
[ "elm1", "elm2" ],
[ "elm3", "elm4", "elm5" ],
[ "elm6" ]
]

// Print sets size.
sets.Length |> printfn "%d"

// Print sets.
sets |> List.iter (printfn "%A")

Console.Read() |> ignore

The code above returns "1" as the length, no matter the amount of elements in the array.
I cannot see why it would, so wondering if anyone got a good explanation?

As a bonus question, what would be a neat way to get the total size? (6 in this case)

.

Note also that there are no arrays in your code. [ ... ] makes a list, not an array.

(See e.g. [link:lorgonblog.spaces.live.com] for more.)

By on 4/12/2009 12:49 PM ()

By using comma ( , ) as separator you declare tuple. So each your list

contains only one tuple element. To declare several element in list you

need to use semicolon ( ; ) as delimeter 

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let sets = [


    [ "elm1"; "elm2" ];


    [ "elm3"; "elm4"; "elm5" ];


    [ "elm6" ]   


]

Bonus answer

1

    sets |> Seq.sum_by Seq.length
By on 4/12/2009 9:02 AM ()

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