From: Logan Capaldo <logancapaldo@...>
Date: 2006-12-19T15:32:45+09:00
Subject: Re: DRYing a loop..

------=_Part_193_26488664.1166509961886
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

On 12/19/06, Josselin <josselin@wanadoo.fr> wrote:
>
> I wrote that the newbie way, but is there any way to DRY it ?
>
>     closed_cities = []
>      0.step(9, 1) do |i|
>        closed_cities  <<  City.find_by_id( city_25 [i] [0] )
>        i = i.next
>      end
>
> if yes, is it only for fun , or does it impact performance (a lot ?)


i = i.next is unecessary, the step method updates the loop for you. Also you
can use upto instead of step:

0.upto(9) do |i|
  closed_cities << City.find_by_id( city_25[i][0] )
end

Or instead of using upto you can use a range:

(0..9).each do |i|
   closed_cities << City.find_by_id( city_25[i][0] )
end

But now you realize, hey if I'm gonna use a range, I can use map, so now you
make your code one line:

closed_cities = (0..9).map { |i| City.find_by_id( city_25[i][0] ) }

I would suggest checking out the docs for Range, as well as for step, upto,
times each and map.

thanks for your lights
>
> joss
>
>
>

------=_Part_193_26488664.1166509961886--