F# defining/using a type/module in another file in the same project

This will hopefully be an easy one. I have an F# project (latest F# CTP) with two files (Program.fs, Stack.fs). In Stack.fs I have a simple namespace and type definition

Stack.fs

namespace Col

type Stack= 
 ...

Now I try to include the namespace in Program.fs by declaring

open Col

This doesn't work and gives me the error "The namespace or module Col is not defined." Yet it's defined within the same project. I've got to be missing something obvious

Best Answer

What order are the files in the project? Stack.fs needs to come before Program.fs for Program.fs to be able to 'see' it.

Related Solutions

R – How to use the F# Reflection library

The F# reflection library was rewritten for either Beta 1 or the CTP. Here is your code slightly changed to use the new library, and to avoid using the F# PlusPack (print_string is for OCaml compatibility).

open Microsoft.FSharp.Reflection

let printTupleValues x =
    if FSharpType.IsTuple( x.GetType() ) then
        let s =
            FSharpValue.GetTupleFields( x )
            |> Array.map (fun a -> a.ToString())
            |> Array.reduce (fun a b -> sprintf "%s, %s" a b)
        printfn "(%s)" s
    else 
        printfn "not a tuple"

printTupleValues ("hello world", 1)

F#: FSharp.PowerPack.dll previous to May 2009 CTP

Briefly,

back when F# was a research project its libraries were full of tons of stuff
now that F# is being 'productized', we have to be more choosy about the stuff that goes in the F# core library (FSharp.Core.dll)
thus the library was partitioned into FSharp.Core and FSharp.PowerPack, where the latter library contains older/experimental/back-compat/OCaml-compat stuff that does not meet the bar for shipping as part of the core library

The error message here is effectively a 'transitional' error message, saying that whereas this stuff used to be a part of FSharp.Core, it got moved, and here's how to find it. Basically we're trying not to break everyone while at the same time reducing the public surface area of the core library.

Best Answer

Related Solutions

R – How to use the F# Reflection library

F#: FSharp.PowerPack.dll previous to May 2009 CTP

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