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reflection - How to find each instance of a class in Ruby

Is there a way to get all the objects that are of a certain class in Ruby?

To clarify:

class Pokemon
end

pikatchu = Pokemon.new
charmander = Pokemon.new

So, is there a way I could somehow retrieve references those two objects (pikatchu and charmander)?

I actually thought of shoving it all into a class array via initialize, but that could potentially grow big, and I am assuming there might be a native Ruby approach to it.

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The solution is to use ObjectSpace.each_object method like

ObjectSpace.each_object(Pokemon) {|x| p x}

which produces

<Pokemon:0x0000010098aa70>
<Pokemon:0x00000100992158>
 => 2 

Details are discussed in the PickAxe book Chapter 25


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