11–20 of 33 posts
For what purpose?
Quoth xkcd, "Tail recusion is its own reward." In all seriousness, even if the y combinator is practically useless in languages that don't have proper TCO (which is specced for ES7), it's a useful learning tool, is powerfully mind expanding, and can help to demonstrate the power of the λ-calculus.
http://blog.klipse.tech/lambda/2016/08/10/y-combinator-app-j...
If I'm not mistaken, this isn't the full Y combinator yet. It's a partial step towards deriving the full Y combinator. (f => (x => x(x))(y => f(x => y(y)(x)))) (func => n => (n === 0) ? 1 : (n * func(n - 1))) (19) Notice that the ugly func(func)(n-1) recursive call with the proper Y combinator simply became func(n-1). The full Y combinator is also vastly more mystical and less obvious than the partial step :)
For what purpose?
Quoth xkcd, "Tail recusion is its own reward." In all seriousness, even if the y combinator is practically useless in languages that don't have proper TCO (which is specced for ES7), it's a useful learning tool, is powerfully mind expanding, and can help to demonstrate the power of the λ-calculus.
For what purpose?
Quoth xkcd, "Tail recusion is its own reward." In all seriousness, even if the y combinator is practically useless in languages that don't have proper TCO (which is specced for ES7), it's a useful learning tool, is powerfully mind expanding, and can help to demonstrate the power of the λ-calculus.
The Y combinator is useless in languages that already have builtin support for recursive functions.
The code samples fail in Safari. The first one prints "SyntaxError: Unexpected token '>'".
(lambda f: f(f))
(lambda fn: lambda n: 1 if n == 0 else (n * fn(fn)(n - 1)))
(5)Earlier quoted context omitted.
Quoth xkcd, "Tail recusion is its own reward." In all seriousness, even if the y combinator is practically useless in languages that don't have proper TCO (which is specced for ES7), it's a useful learning tool, is powerfully mind expanding, and can help to demonstrate the power of the λ-calculus.
Is the Y-combinator any more or less dependent on TCO than regular recursion? The Y combinator is useless in languages that already have builtin support for recursive functions.
You can do elegant recursive memoization with the Y combinator as explained here http://blog.klipse.tech/lambda/2016/08/10/y-combinator-app-j...
I find the Python implementation is slightly more elegant: (lambda f: f(f)) (lambda fn: lambda n: 1 if n == 0 else (n * fn(fn)(n - 1))) (5)
The code samples fail in Safari. The first one prints "SyntaxError: Unexpected token '>'".
(function (f) {
return f(f);
})(function (func) {
return function (n) {
return n === 0 ? 1 : n * func(func)(n - 1);
};
})(19);