From: Fear Dubh <feardubh@...>
Date: 2005-02-28T04:54:58+09:00
Subject: Re: for vs. each

Hi,

"Robert Klemme" <bob.news@gmx.net> wrote in message
news:38ea7eF5o769pU1@individual.net...
>
> "Fear Dubh" <feardubh@spam.spam> schrieb im Newsbeitrag
> news:cvslbj$9ns$1@reader01.news.esat.net...
> >
> > "ts" <decoux@moulon.inra.fr> wrote in message
> > news:200502271128.j1RBSA019680@moulon.inra.fr...
> >> >>>>> "F" == Fear Dubh <feardubh@spam.spam> writes:
> >>
> >> F> Is there a difference between:
> >> F>   for foo in bar do ...
> >> F> and
> >> F>   bar.each do |foo| ...
> >>
> >> uln% ruby -e 'for a in [12] do end; p a'
> >> 12
> >> uln%
> >>
> >> uln% ruby -e '[12].each do |a| end; p a'
> >> -e:1: undefined local variable or method `a' for main:Object
(NameError)
> >> uln%
> >>
> >>
> > Thanks!
> >
> > Does each have a fatter frame then?
> > Is "for ... in ... do ..." more efficient?
>
> I would believe not, but you can test this yourself (hint "ruby -r
profile"
> and module Benchmark).
>
> Indenpendently of that I strongly recommend the usage of "each" as it is
> used 99% of the cases and it's simply standard.  Although it's not an
> enforced convention, people will expect that and it makes everybody's life
> easier to stick to some conventions.
>
OK, Thanks,

Now I feel like a bold child, scolded for stuffing my face
with this delicious syntax sugar! :-)

I have a further question:
As ts showed "for ... in ... do" is not exactly the same as "... each do
....",
so is there an "un-sugared" expression that is equivalent to "for ..."?
Is there any circumstance where it would be better to use "for"?

> Kind regards
>
>     robert
>
Regards

--Fear Dubh