Apologies if this has been asked before.

Note I have also asked this over at Stack Overflow at [link:stackoverflow.com]

If I have a discriminated union as follows:-

type Foo =

| A of string

| B of int

| C of char

Is it possible to write a function, DefaultFoot, of type ('a -> Foo) -> Foo(default value of 'a), i.e. a function which can input a function of type ('a -> Foo) and output a Foo.A or Foo.B or Foo.C as appropriate, with value set to the default value of the appropriate type, e.g.:-

let bDefault = B |> DefaultFoo

is equivalent to:-

let bDefault = B(0)

Currently I am doing this by writing a bunch of individual functions:-

let defaultA = A(null)

let defaultB = B(0)

let defaultC = C('\u0000')

etc.

I know this is probably a rather stupid question, however I want to see whether it isn't possible to use the former, elegant, approach rather than the rather less elegant latter approach.

Thanks in advance!