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How to map String.split over a seq<String>?
f#

I am learning F# from Jon Harrop's `F# for Scientists` book, and have found that while a great learning tool some of the examples are a bit out of date with the current release of the language.

I'm currently using VS2008 Shell with F# 2.0 build 1.9.9.9 (and the associated PowerPack). I am running into trouble with the following example for reading a matrix from a text file when trying to parse the strings into tokens:

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let read_matrix filename
  line_of_file filename
  |> Seq.map (String.split [' '])
  |> Seq.map (Seq.map float)
  |> Matrix.ofSeq;;

I get an error (both through fsi and via intellisense in VS) that points to split not being defined.
"error FS0039: The value, constructor, namespace or type 'split' is not defined"

As a bonus question, how do I get the interactive editor (Intellisense) to load/be aware of modules in the PowerPack DLL? Thanks everyone.

.

I don't recall if String.split is still in the PowerPack, but you can always use System.String.Split:

[link:msdn.microsoft.com]

instead.

As for intellisense in the editor:

- in a .fsx (script) file, the references from "#r"-ed assemblies will be used to populate intellisense

- in a .fs file in a project, the project references will be used ('add reference')

By on 4/19/2010 2:08 PM ()

I don't recall if String.split is still in the PowerPack, but you can always use System.String.Split:

Well, after some more work, I found that String.split is still in PowerPack.Compatibility for OCaml-related reasons (I assume) and I can make it work that way.

However, that doesn't feel quite like the "right" way to go about this. I tried using System.String.Split, but am told by the interpreter/compiler that "error FS0492: Split is not a static method" Am I just missing something very basic? I tried running the code on an instantiated object so that it wouldn't need to call a static method, but had little success. The MSDN page didn't have any specific F# examples, so I am wondering if

I am just doing something boneheaded and not seeing it while I tinker.

As for intellisense in the editor:

- in a .fsx (script) file, the references from "#r"-ed assemblies

will be used to populate intellisense

- in a .fs file in a project, the project references will be used

('add reference')

Ahh, good to know, thanks!

By on 4/19/2010 2:37 PM ()

Thanks, this did it.

Referencing PowerPack.dll alone didn't remedy the issue.

By on 4/22/2010 8:33 PM ()

Ah, oops, it's an instance method and I didn't notice. This works:

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let strings = ["hello world"; "foo bar baz"; "Brian"]
let result = 
    strings
    |> Seq.map (fun s -> s.Split([|' '|], System.StringSplitOptions.RemoveEmptyEntries))
printfn "%A" result
By on 4/19/2010 2:54 PM ()

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