From: dblack@...
Date: 2006-03-23T01:24:20+09:00
Subject: Re: why doesn't "to_s" DWIM?

Hi --

On Thu, 23 Mar 2006, Chris McMahon wrote:

>
> How come to_s doesn't work here?
>
> ####################################
> require 'test/unit'
> class TOY_CASE<Test::Unit::TestCase
>
> def test_toy_test
>
> aoa = [[1,2,3],[4,5,6]]
>
> aoa.each do |arr|
> 	arr.each do |item|
> 		item = item.to_s
> 		end
> 		assert_equal(["1","2","3"],arr)
> end
>
>
> end #def
> end #class
> ##########################################

Inside the inner each block, you're just doing a local (re)assignment
to "item".  There's no connection to the object that used to be in
item, except that that object happens to be part of the rhs.

You can achieve what you want with this:

   aaa.each do |arr|
     arr.map! do |item|
       item.to_s
     end
   end

That will go through each inner array and replace the current item
with what's in the block (namely, item.to_s).


David

-- 
David A. Black (dblack@wobblini.net)
Ruby Power and Light, LLC (http://www.rubypowerandlight.com)

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