override rassoc

gistfile1.rb

class Array
  def rassoc obj, place=1
    if place
      place = place.to_i rescue -1
      return if place < 0
    end

    self.each do |item|
      next unless item.respond_to? :include? 

      if place
        return item if item[place]==obj
      else
        return item if item.include? obj
      end
    end

    nil
  end
end

array = ["apple", "orange", "lemon"] 
array2 = [["apple", "good taste", "red"], ["orange", "bad taste", "orange"], ["lemon" , "no taste", "yellow"]]

Hash[ array.map{ |fruit| [fruit, array2.rassoc(fruit, nil)]}]

array2 = [["good taste", "red", "apple"], ["no taste", "lemon", "yellow"], ["orange", "bad taste", "orange"]]

Hash[ array.map{ |fruit| [fruit, array2.rassoc(fruit, nil)]}]