try to avoid use try catch statement and manage the error in await call

await-manage-cacth-without-try.js

const to = promise =>{
	return promise.then(data =>{
			return [null, data]
		})
		.catch(err => [err])
}

fetchData(){
  let err, data
  [err, data] = await to(Api.getEntity())
	 
  if (err) { throw new Error(err)}
	 
	return new Entity(data)
}