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rubyenumerator

ArgumentError in #new, Subclassing Enumerator


I'm subclassing Enumerator like this:

class CuadraticPrimeGenerator < Enumerator
  def initialize(a=1,b=49)
    super do |y|
      x = 1
      loop do 
        y << x**2 + a*x + b
        x += 1
      end
    end
  end
end

However...

> CuadraticPrimeGenerator.new(1,49)
0027.rb:41:in `initialize': 49 is not a symbol (TypeError)
    from 0027.rb:41:in `initialize'
    from 0027.rb:48:in `new'
    from 0027.rb:48:in `<main>'

Thoughts?


Solution

  • What about:

    class CuadraticPrimeGenerator < Enumerator
      def initialize(a=1,b=49)
        super() do |y|
          count, x = 0, 1
          loop { y.yield(x**2 + a*x + b) }
        end
      end
    end