From: dblack@...
Date: 2006-02-13T06:54:09+09:00
Subject: Re: newbie question about blocks

Hi --

On Mon, 13 Feb 2006, Jeppe Jakobsen wrote:

> Hi, I want to square every element in my array using a block:
>
> a = (1..1000).to_a
> a.each {|x| x**2}
>
> But this does not seem to work, it just outputs my array completely
> unchanged :(

What you want is map, rather than each:

   a.map {|x| x**2 }

each just returns the receiver (i.e., the array itself).  map returns
a new array, composed of the results obtained by running the block
once for each item.

"collect" is a synonym for map.


David

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

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