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How to use a function defined below
f#

Hello

I'm new here

I have a problem using functions defined below.

For example: (This example does not have any real meaning but showing the problem)

let x(a:int) =

match (a) with

| 0 -> 5:int

| _ -> y(a-1):int

let y (b:int) =

match (b) with

| 0 -> 6:int

| _ -> x(b-1)

I tried using (rec) but it didn't work

and reordering function doesn't solve the problem

and PLEASE HELP ME!!!!!!!!

.

To define mutually recursive functions, use "let rec x ... and y ..." - the key is changing the second "let" to "and".

By on 11/30/2008 9:56 PM ()

Does F# support tail call optimization in this case(mutually recursive functions) ?

By on 12/1/2008 1:12 AM ()

Yes; the F# compiler will often turn a directly recursive function into a loop, but all tail calls are emitted with the .tail IL instruction, so code like the above will not stack overflow. (Try it: 

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#light

let rec even n =
    if n = 0 then true
    else odd (n-1)
and odd n =
    if n = 0 then false
    else even (n-1)

printfn "%A" (even 1000000)

)

By on 12/1/2008 1:28 AM ()

Thank you very much

it worked!!

By on 12/1/2008 12:35 AM ()

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