Y combinator: Difference between revisions
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→{{header|F Sharp|F#}}
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test("fac")
test("fib")</syntaxhighlight>
=={{header|Binary Lambda Calculus}}==
This BLC program outputs 6!, as computed with the Y combinator, in unary (generated from https://github.com/tromp/AIT/blob/master/rosetta/facY.lam) :
<pre>11 c2 a3 40 b0 bf 65 ee 05 7c 0c ef 18 89 70 39 d0 39 ce 81 6e c0 3c e8 31</pre>
=={{header|BlitzMax}}==
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=={{header|F Sharp|F#}}==
===March 2024===
In spite of everything that follows I am going to go with this.
<syntaxhighlight lang="fsharp">
// Y combinator. Nigel Galloway: March 5th., 2024
type Y<'T> = { eval: Y<'T> -> ('T -> 'T) }
let Y n g=let l = { eval = fun l -> fun x -> (n (l.eval l)) x } in (l.eval l) g
let fibonacci=function 0->1 |x->let fibonacci f= function 0->0 |1->1 |x->f(x - 1) + f(x - 2) in Y fibonacci x
let factorial n=let factorial f=function 0->1 |x->x*f(x-1) in Y factorial n
printfn "fibonacci 10=%d\nfactorial 5=%d" (fibonacci 10) (factorial 5)
</syntaxhighlight>
{{output}}
<pre>
fibonacci 10=55
factorial 5=120
</pre>
===Pre March 2024===
<syntaxhighlight lang="fsharp">type 'a mu = Roll of ('a mu -> 'a) // ' fixes ease syntax colouring confusion with
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#'
fixp.Y <- \ (f) (\ (x) (x) (x)) (\ (y) (f) ((y) (y))) # y-combinator
fixp.Z <- \ (f) (\ (x) (x) (x)) (\ (y) (f) (\ (...) (y) (y) (...))) # z-combinator
</syntaxhighlight>
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</syntaxhighlight>
You can verify these codes by [https://shinylive.io/r/editor/#code=NobwRAdghgtgpmAXGAZgSwB5wCYAcD2aEALgHQBOYANGAMb4lwlJgDEA5AAQCanAvJ0DdwClIAKQQGdSEiQEpxGUilEYMs2QB0IHTgC1+
=={{header|Racket}}==
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