geo_coordinate.rb

def GeoCoordinate(*args)
  case args.first
  when String
    GeoCoordinate.new(*args[0].to_i, *args[1].to_i)
  when Array
    GeoCoordinate.new(*args[0][0], *args[1][0])
  when Hash
    GeoCoordinate.new(*args[0][:latitude], *args[0][:longitude])
  when ->(arg) { %w(Float Fixnum).include?(arg.class.to_s) }
    GeoCoordinate.new(*args)
  when ->(arg) { arg.respond_to?(:to_geo_coordinate) }
    args.first.to_geo_coordinate
  when ->(arg) { arg.is_a?(Latitude) }
    GeoCoordinate.new(*args[0].to_i, *args[1].to_i)
  else
    raise TypeError, "Cannot convert #{args.inspect} to GeoCoordinate"
  end
end

GeoCoordinate(55.45, 37.37)
GeoCoordinate('55.45', '37.37')
GeoCoordinate(['55.45'], ['37.37'])
GeoCoordinate(MagicCoordinate.new)
GeoCoordinate(Latitude.new('55.45'), Longitude.new('37.37'))
GeoCoordinate(latitude: '55.45', longitude: '37.37')