From: Tim Hunter <TimHunter@...>
Date: 2008-02-10T07:19:52+09:00
Subject: Re: Identifying

Adam Akhtar wrote:
> Farrel Lifson wrote:
> 
>> Use a case statement:
>>
>>   array.each do |x|
>>     case x
>>       when Array: do something
>>       when Integer: do something
>>     end
>>   end
> 
> is
> 
> when Array: do something
> 
> a valid statement??
> 
> is
> 
> if x == Array
> 
> also a valid statement??
> 
> i was expecting having to use something like x.is_a as Stefano said.


when Array:

is valid in the context of a case expression.

if x == Array

is also valid, but will only be true if x is in fact Array, that is

x = Array
if x == Array # will be true

For all other things, it will be false.

Here's an online copy of the 1st Edition of _Programming_Ruby_, which 
will help answer these questions: 
http://www.ruby-doc.org/docs/ProgrammingRuby/


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