Go rant

[Ary Borenszweig]

Andrei Alexandrescu wrote:
> bearophile wrote:
>> Walter Bright:
>>> Ain't that cool? But look closer. The advantage of quicksort is
>>> that it is an *in-place* sort. The Haskell one creates new arrays
>>> for every state in the sort. The other fundamental problem with the
>>> Haskell version is that it selects the first array element as the
>>> "pivot". This is the worst choice, since arrays to be sorted tend
>>> to already be mostly sorted, and quicksort gives quadratic
>>> performance to sort an already sorted array with the first element
>>> as the pivot.
>>
>> You are missing two big things, Walter:
>>
>> 1) The first one is big: that was not an example of a general-purpose
>> sort routine to be used to sort items. If you go look at how normal
>> system sort is done in Haskell you will see a much longer and much
>> more efficient implementation. The point of that example was to show
>> how you can compactly express a computational idea in Haskell, in a
>> safe, very compact and readable enough way. In a normal program a
>> significant percentage of the code doesn't need to be top
>> performance, in both runtime performance and memory used, because
>> it's used rarely and/or on small data sets. So for this code it's not
>> good to write an extremely efficient implementation, it's better to
>> use a safe, very compact and readable implementation. Haskell gives
>> you both safety and compact code. Note that for real sorting purposes
>> you don't use that onliner, you use some kind of system sort. So what
>> I am says applies to new code, absent in the standard library.
> 
> It's a piece of crap. A crappy example is a crappy example is a crappy
> example. It consistently does more harm than good.

What's that argument?