From: dblack@...
Date: 2006-02-28T23:06:23+09:00
Subject: Re: Same variable name used in block and local question

Hi --

On Tue, 28 Feb 2006, rubyrus wrote:

> Can anybody help me here, TIA!!
>
> This is the code.  I expect to see the string "Afterward:turkey", but
> why am I getting "Afterward:camel"?  |animal| parameter in a block
> should be temporary inside the block, right??
>
>
> Code:
> ----------
> animal = "turkey"
>
> puts "Original:" + animal
> puts
>
> ["cow","camel"].each { |animal| puts "in block:" + animal }
>
> puts
> puts "Afterwards:" + animal
>
>
> Output:
> -----------
> Original:turkey
>
> in block:cow
> in block:camel
>
> Afterwards:camel

Block parameters actually use assignment semantics, so if a variable
already exists, it gets assigned to.  The animal in the pipes is the
same as the animal before the block.  If you use a new local variable,
it will come into being just for the block.

Before a hundred-message thread gets spawned, let me add that yes,
it's going to change in 2.0 :-)  I'm actually one of the few people
who like it the way it is, but Matz has said that he considers it a
design mistake and wants to change it.


David

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

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