/**
- An standard callback. It can use for both async and ansync action
- All of callback in module must use that type as standard. It will make
easy to write and handle async callback
@callback StdCallback
@param {object} error Error occur during perform async action
@param {object} result Result from action
@example
// this is instance of StdCallback
function queryCallback(err, items) {
// handle error
if (err) {
// do some thing to handle error here
return
}
// other action with items from database
console.log(items)
}
asynQuery(queryCallback)
*/