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A comment on Ask HN: What is the most beautiful piece of code you've ever read?. Parent comment

Re:Ask HN: What is the most beautiful piece of code you've e... by cakoose on Monday October 28, 2019 @04:26AM (#21375176)
> In almost every other language this code would look messy or use some terrible recursion.

Nah, lots of other languages can do this.

Python:

    def factorial(i):
        return reduce(operator.mul, range(2, i+1), 1)
Ruby:

    def factorial(i)
        (2..i).reduce(1, :*)
    end
Haskell:

    factorial n = foldl (*) 1 [2..n]
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Re:Ask HN: What is the most beautiful piece of code you've e... by estomagordo on Monday October 28, 2019 @05:14AM (#21375385)
For Python, we don't need to supply the optional initializer 1. And reduce resides in the functools namespace (much like mul is in operator). I assume we're not talking about that peculiar dialect of Python that is no longer supported a few months from now.
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Re:Ask HN: What is the most beautiful piece of code you've e... by messe on Monday October 28, 2019 @07:03AM (#21375866)
Not only that but in python 3.8, it can be written:

    def factorial(n):
        return math.prod(range(1,n+1))
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Re:Ask HN: What is the most beautiful piece of code you've e... by estomagordo on Monday October 28, 2019 @07:53AM (#21376075)
Nice!
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Re:Ask HN: What is the most beautiful piece of code you've e... by cakoose on Monday October 28, 2019 @05:07PM (#21381681)
> For Python, we don't need to supply the optional initializer 1.

Without the initializer, factorial(0) doesn't work.

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Re:Ask HN: What is the most beautiful piece of code you've e... by rnhmjoj on Monday October 28, 2019 @04:35AM (#21375203)
In haskell you can also use the `product` function:

    factorial n = product [1..n]
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