From: David Alan Black <dblack@...>
Date: 2000-12-03T20:48:43+09:00
Subject: [ruby-talk:6762] Re: Array Intersect (&) question

On Sun, 3 Dec 2000, Clemens Hintze wrote:

>     matz> Using a hash makes it pretty fast, but it does not preserve
>     matz> the original order.  If no one requests order preservation,
>     matz> I will use hashes in &, |, and uniq.  What's your opinion?
> 
> for me this would be ok! If I want to rely on order, I would simply
> order it afterwards. The operators &, | are SET operations. In a set
> neither the order nor the cound is important!
> 
> So I have to confess that every time I used them, I had ordered my
> results anyway, as I did not assume any order. So that there is an
> order here violates my POLS ;-)
> 
> Speed is an issue here, IMHO.

I agree.  Even if & and | ignore order, there are still ways to order
the data -- no functionality is lost.  If they sacrifice speed, that's
a lot harder to make up for.


David

-- 
David Alan Black
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