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# When mathn is required Rational is changed to simplify the use of Rational

# operations.

#

# Normal behaviour:

#

#   Rational.new!(1,3) ** 2 # => Rational(1, 9)

#   (1 / 3) ** 2            # => 0

#

# require 'mathn' behaviour:

#

#   (1 / 3) ** 2            # => 1/9

class Rational

  remove_method :**

  ##

  # Exponentiate by +other+

  #

  #   (1/3) ** 2 # => 1/9

  def ** (other)

    if other.kind_of?(Rational)

      other2 = other

      if self < 0

        return Complex(self, 0.0) ** other

      elsif other == 0

        return Rational(1,1)

      elsif self == 0

        return Rational(0,1)

      elsif self == 1

        return Rational(1,1)

      end

      npd = numerator.prime_division

      dpd = denominator.prime_division

      if other < 0

        other = -other

        npd, dpd = dpd, npd

      end

      for elm in npd

        elm[1] = elm[1] * other

        if !elm[1].kind_of?(Integer) and elm[1].denominator != 1

          return Float(self) ** other2

        end

        elm[1] = elm[1].to_i

      end

      for elm in dpd

        elm[1] = elm[1] * other

        if !elm[1].kind_of?(Integer) and elm[1].denominator != 1

          return Float(self) ** other2

        end

        elm[1] = elm[1].to_i

      end

      num = Integer.from_prime_division(npd)

      den = Integer.from_prime_division(dpd)

      Rational(num,den)

    elsif other.kind_of?(Integer)

      if other > 0

        num = numerator ** other

        den = denominator ** other

      elsif other < 0

        num = denominator ** -other

        den = numerator ** -other

      elsif other == 0

        num = 1

        den = 1

      end

      Rational(num, den)

    elsif other.kind_of?(Float)

      Float(self) ** other

    else

      x , y = other.coerce(self)

      x ** y

    end

  end

end

##