do you think the factorial can benefit from a `tailrect` function? ```var result = 1 for (i in 1..a)...

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[elect]

do you think the factorial can benefit from a tailrect function?

var result = 1
for (i in 1..a)
    result *= i
result

[Mohsen Kashi]

Yess!
For factorial No!
Because we don't need to implement it as recursive.
using tail-rec reduces memory usage of stack(comparing traditional recursive).
To implement it in tail-rec, the method call should be return statement

[elect]

yes or no, then?

[Mohsen Kashi]

Not for factorial. I was wrong at first

[Mohsen Kashi]

actually, it will be the same, with or without tail-rec

[Mohsen Kashi]

If your question is that can we? yes, we can use. But, if your question is it better to use tail-rec? the answer is no preferences

[marstran]

Well, you can implement factorial as a tail recursive function too, but it will overflow the Long so quickly that it doesn't make that much sense to do it. You cannot get a StackOverflowException with it though.

fun factorial(n: Long): Long {
    tailrec fun fact(acc: Long, curr: Long): Long = 
        if (curr == 1L) acc
        else fact(acc * curr, curr - 1L)
    
    return fact(1, n)
}

[serebit]

could always just use reduce instead, like (1..a).reduce { product, next -> product * next }