From: Jano Svitok <jan.svitok@...>
Date: 2008-03-02T07:38:44+09:00
Subject: Re: counting in for .. in ..

On Sat, Mar 1, 2008 at 11:24 PM, Daniel Liebig <d.liebig@wevin.de> wrote:
> Hi,
>
>  i'm doing my first steps in ruby (on rails) and often use things like
>
>  for thing in @several_things
>   print thing
>  end

Let's start with equivalent code:

@several_things.each do |thing|
   print thing
end

>  Ok so far, looks great :)
>
>  But i often need a counter inside of the loop, may it be to create row
>  colors or other stuff. What i end up with then is:
>
>  i = 0
>  for thing in @several_things
>   print thing + " No. " + i.to_s
>   i += 1
>  end

Now let me introduce Enumerable module, that contains each_with_index:

@several_things.each_with_index do |thing, i|
   print "#{thing} No. #{i}"
end

Note: #{expression} is replaced with expression.to_s (more or less)
Lookup Enumerable in the docs, it contains lots of useful stuff.

>  Pardon me, but this is ugly, compared to the first clean lines. So far i
>  know ruby as an elegant language, so i wouldn't be surpised if there'd
>  be any kind of implemented counter in the for loop or a smarter way to
>  implement it.
>
>  Any hints?
>
>  Thanks a lot for any help!
>  R.D.
>  --
>  Posted via http://www.ruby-forum.com/.
>
>