Ruby CastingStruct, taken from https://coderwall.com/p/e2qr2w/structs-with-type-casting-in-ruby

casting_struct.rb

class CastingStruct < Struct
    def self.new(hash, &blk)
        super(*hash.keys) do
            define_method :initialize do |*args|
                super *hash.values.map { |method|
                    args.shift.public_send method
                }
            end
            class_eval(&blk) if blk
        end
    end
end

Person = CastingStruct.new name:     :to_s, 
                           age:      :to_i,
                           category: :to_sym, 
                           wage:     :to_f

people = CSV.parse(data).map { |args| Person.new(*args) }

people.first
# => #<struct Person name="Dave", age=32, category=:employee, wage=15.75>
people.first.category.class
# => Symbol