From: "Mauricio Fernández" <batsman.geo@...>
Date: 2002-12-02T20:21:22+09:00
Subject: Re: Array !== Array?

On Mon, Dec 02, 2002 at 07:20:05PM +0900, Tim Bates wrote:
> What is the rationale behind Array === Array (or indeed any other class) being 
> false? Array.new === Array is also false. How do I test what class some 
> object is in a case statement?

irb(main):001:0> a = []
[]
irb(main):002:0> case a
irb(main):003:1> when Array
irb(main):004:1> puts "Array"
irb(main):005:1> when Hash
irb(main):006:1> puts "Hash"
irb(main):007:1> end
Array
nil

ie, in 
	case a
	when B
		...
	when C
		...
	end
the comparison being done is B === a, not a === B.
It just makes sense that 
irb(main):008:0> Array === Array.new
true

And of course
irb(main):009:0> Array === Array
false

because Array is not an instance of class Array but of class Class
irb(main):010:0> Class === Array
true


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