Struct

Question=Struct.new(:question, :answer)
=> Question
q1=Question.new("what's your first name?","subbu")
=> #
q1.question (behaves like an object)
=> "what's your first name?"
q1[:question] (behaves like a symbol)
=> "what's your first name?"
q1['question'] (behaves like a hash)
=> "what's your first name?"
q1[0] (behaves like an array)
=> "what's your first name?"
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This means, I can treat my Struct based on what the situation demands. Sometimes I can treat it like an array or a hash or an object or a symbol.