Variadic fixed-point combinator: Difference between revisions

=={{header|Python}}==

A re-translation of the Wren version.

<syntaxhighlight lang="python">Y = lambda a: [(lambda x: lambda: x(Y(a)))(f) for f in a]

even_odd_fix = [

lambda f: lambda n: n == 0 or f[1]()(n - 1),

lambda f: lambda n: n != 0 and f[0]()(n - 1),

]

collatz_fix = [

lambda f: lambda n, d: d if n == 1 else f[(n % 2)+1]()(n, d+1),

lambda f: lambda n, d: f[0]()(n//2, d),

lambda f: lambda n, d: f[0]()(3*n+1, d),

]

even_odd = [f() for f in Y(even_odd_fix)]

collatz = Y(collatz_fix)[0]()

for i in range(1, 11):

e = even_odd[0](i)

o = even_odd[1](i)

c = collatz(i, 0)

print(f'{i :2d}: Even: {e} Odd: {o} Collatz: {c}')

</syntaxhighlight>