once method

  1. @Deprecated('Use snapshot() instead')
TTLink once(
  1. TTOnCb cb
)

Get the current data without subscribing to updates. Or undefined if it cannot be found.

@param cb The data is the value for that link at that given point in time. And the key is the last property name or ID of the node. @returns same link context

Implementation

@Deprecated('Use snapshot() instead')
TTLink once(TTOnCb cb) {
  snapshot().then((val) => cb(val, key));
  return this;
}