Split F# modules across multiple files

Question

Is it possible to split an F# module across files?

According to the book I have it is, but the book is probably outdated (Foundations of F#)

Answer 1

Like Kurt says, you can add extension methods to types, and thus

// File1.fs
namespace Foo

type Mine() =
    static member f1 () = ()

then

// File2.fs
type Foo.Mine with
    static member f2() = ()

Foo.Mine.    // both f1 and f2 here

Since it's a class and not a module, you lose the ability to do 'open Mine' (but gain the ability to overload); thus this may or may not be an acceptable alternative for you depending on exactly what you're doing.