Reconciliation chapter spends a good time explaining why using the index or even Math.random() as a key is a bad idea, proceeding to suggest using an existent id as a key. When there's not an existent id, it's suggested to "add a new ID property to your model or hash some parts of the content to generate a key".
That's a very controversial issue, a lot of people do it wrong. An example of how to do it would make the chapter a lot better. It's an extensive chapter (compared to others) that seems to end up with no code conclusion.
Reconciliation chapter spends a good time explaining why using the index or even
Math.random()as a key is a bad idea, proceeding to suggest using an existent id as a key. When there's not an existentid, it's suggested to "add a new ID property to your model or hash some parts of the content to generate a key".That's a very controversial issue, a lot of people do it wrong. An example of how to do it would make the chapter a lot better. It's an extensive chapter (compared to others) that seems to end up with no code conclusion.