var response_status = new Object;

// Initialize the data structure used to track the status of a page's initial AJAX calls.
function initialize_data_ready_states(signifier_array) {
  for( var index = 0; index < signifier_array.length; index++ ){
    response_status[signifier_array[index]] = false;
  }
}


// Set an element of the data structure used to track the status of a page's initial AJAX calls.
function set_data_ready_state(signifier, state) {
  response_status[signifier] = state;
}


// Check to see if a page has completed all initial AJAX calls.  Optionally pass in
// a data ready state pair.
function data_is_ready(signifier, state) {
  if( arguments.length == 2 )  set_data_ready_state(signifier, state);
  var is_ready = true;
  for( var signifier in response_status )  is_ready &= response_status[signifier];
  return is_ready;
}