Callback functions for `start` and `end` receive the id of the * transaction as a first argument. For `complete`, `success`, and * `failure`, callbacks receive the id and the response object * (usually the XMLHttpRequest instance). If the `arguments` * property was included in the configuration object passed to * `Y.io()`, the configured data will be passed to all callbacks as * the last argument.
*Callback functions for `start` and `end` receive the id of the transaction as a first argument. For `complete`, `success`, and `failure`, callbacks receive the id and the response object (usually the XMLHttpRequest instance). If the `arguments` property was included in the configuration object passed to `Y.io()`, the configured data will be passed to all callbacks as the last argument.