20 lines
384 B
JavaScript
20 lines
384 B
JavaScript
// The Y combinator, applied to the factorial function
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function factorial(proc) {
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return function (n) {
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return (n <= 1) ? 1 : n * proc(n-1);
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}
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}
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function Y(outer) {
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function inner(proc) {
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function apply(arg) {
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return proc(proc)(arg);
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}
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return outer(apply);
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}
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return inner(inner);
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}
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print("5! is " + Y(factorial)(5));
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