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Is there any way to declare mutually dependent classes in F#?
f#classes

What I want to do is something like:

File a.fs:

type A(...) =
let mutable b: B option = None // error here because B is not known to the compiler
...

File b.fs:

type B(...) =
let a: A = ...
...

I've tried creating file b.fsi and putting it before a.fs in the project, in a attempt to "forward declare" type B, but this seems to have no effect. I've also tried putting both type definitions in a single file separated by "and", but this gives a syntax error.

Any help is greatly appreciated!

.

Putting both in one file works for me:

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type A() =
    let mutable b: B option = None

and B() =


    let a: A = A()

Note that the "and" replaces the "type" and any attributes, e.g. "[<AbstractClass>]", come after the "and".

By on 8/14/2008 4:03 AM ()

Thanks, that worked (I didn't realise that 'and' replaced the second 'type').

Is there no way I can put the two types in different files? They are rather large, and I think there will be more dependent types associated with them in future. It would be a shame to have to put most of the program in a single file.

By on 8/14/2008 6:19 AM ()

As far as I know you can't put mutually dependent types in different files. You also can't split modules over multiple files. You can split namespaces over multiple files, though only types can be put directly into namespaces.

By on 8/14/2008 9:21 AM ()

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