From: Lars Haugseth <ruby-talk@...>
Date: 2012-06-30T22:24:21+09:00
Subject: Re: stack level too deep for quicksort code

On 06/30/2012 03:09 PM, Jan E. wrote:
> Lars Haugseth wrote in post #1066738:
>> The only time the array is referenced later in the method is when you
>> partition all except the first element, so it makes perfect sense to me.
>
> I'm talking about the original array you want to sort. When you pass it
> to the method, it will lose its first element:
>
> my_array = [3, 1, 5, 2]
> sorted = quicksort(my_array)  # get a sorted copy
> p my_array  # WTF? my_array has suddenly become [1, 5, 2]
>
> I'd actually call this a bug. The method should either sort the original
> array, or it should not touch the original array at all and only return
> a new sorted array. I think the second option makes more sense for a
> function style method.
>
> But your method would return a new sorted array and at the same time
> somewhat corrupt the original one.

Ah, now I see what you mean. Good call.

-- 
Lars Haugseth