gistfile1.rb

      # for some reason the closure doesn't have access to class variables
      lon = params[:x]; lat = params[:y]; zoom = params[:zoom]; city = current_quest.city.code; 
      width = params[:width].to_f; height = params[:height].to_f
      current_quest.primary_window = GeoLocation.new do 
#        self.lon = params[:x]; self.lat = params[:y]; self.zoom = params[:zoom] 
        puts "width: #{width}"
        puts "lat: #{lat}"
        self.lon = lon; self.lat = lat; 
        self.width = width; self.height = height; 
        self.zoom = zoom; self.city = city
      end
      puts "LAT: #{current_quest.primary_window.lat}"
      puts "WIDTH: #{current_quest.primary_window.width}"
      current_quest.save unless current_quest.anonymous?

class GeoLocation
    attr_accessor :lon, :lat, :width, :height, :zoom, :zip, :city, :state, :zip, 
      :precision, :dist_from_home, :string_as_geocoded, :geo_postal, :geo_street_address, :geo_city, :geo_state
    def initialize(&block)
      instance_eval(&block)
    end
...
end


Output:
width: 0.316406250000023
lat: 37.754972691904946
LAT: 37.754972691904946
WIDTH: