From: Robert Dober <robert.dober@...>
Date: 2007-08-24T20:29:33+09:00
Subject: Re: something I just found out, am sharing (:newbish)

On 8/24/07, David A. Black <dblack@rubypal.com> wrote:
> Hi --

>
> Don't worry -- there's no Academie Anglaise :-)
I am not French, only my wife is;), but it is a funny remark.
>
> > But seriously there is just no need to pay the cost of the
> > construction of another String / Array.
> > Performance difference is already enormous for moderately long strings :
>
> It depends, though; sometimes you might want a copy, sometimes you
> might definitely not. So the + vs. << decision may not be premature,
> and the right decision may not even be the optimizing one :-)
Hmm David when one does
 a += b
the copy is thrown away and you have the same semantics (save some
implicit calls to to_s) as for
 a << b
My benchmarks show some dramatic performance degradation already but
imagine the GC kicking in because of the temporary copies, no,
honestly I feel that beginners
should be warned about that idiom.

For sure sometimes you want
 a = b + c
but that is a different story.

Robert

-- 
I'm an atheist and that's it. I believe there's nothing we can know
except that we should be kind to each other and do what we can for
other people.
-- Katharine Hepburn