Y combinator: Difference between revisions

\\ y() return value. no use of closure

y=lambda (g, x)->g(g, x)

Print y(lambda (g, n as decimal)->if(n=0->1, n*g(g, n-1)), 10)=3628800 ' true

Print y(lambda (g, n)->if(n<=1->n,g(g, n-1)+g(g, n-2)), 10)=55 ' true

\\ Using closure in y, y() return function

y=lambda (g)->lambda g (x) -> g(g, x)

fact=y((lambda (g, n as decimal)-> if(n=0->1, n*g(g, n-1))))

Print fact(6)=720, fact(24)=620448401733239439360000@

fib=y(lambda (g, n)->if(n<=1->n, g(g, n-1)+g(g, n-2)))

Print fib(10)=55

}

\\ all lambda arguments passed by value in this example

\\ There is no recursion in these lambdas

Y combinator make argument f \\as m(mclosure, argument) pass as first argument a copy of mf

\\ so never a function, here, call itself, only call a copy who get it as argument before the call.

fac_step =lambda f (m, nx)-> {f(f,x)

fac=lambda (n) -> {

if n<2 then {=1 else =n*Lambda(n-1)