Mongoid::Fields.option :delegate do |model, field, options| options = {} unless options.kind_of?(Hash) x_meth = options[:x] || :x y_meth = options[:y] || :y model.instance_eval do define_method x_meth do self[field.name][0]; end define_method y_meth do self[field.name][1]; end define_method "#{x_meth}=" do |arg| self[field.name][0] = arg end define_method "#{y_meth}=" do |arg| self[field.name][1] = arg end # model.class_eval do # define_method "close_to" do |*args| # queriable.where(field.name.near_sphere => *args) # end # end end end