binary_calc.rb

class BinaryCalc
  def initialize(arg1, arg2, operation)
    @arg1 = arg1.to_s
    @arg2 = arg2.to_s
    @operation = operation == 'plus' ? :+ : :-
  end

  def call
    (@arg1.to_i(2).public_send(@operation, @arg2.to_i(2)).to_s(2))
  end
end