update README

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Mathew Polzin
2018-12-05 17:30:48 -08:00
parent 35d6cbb440
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@@ -186,9 +186,11 @@ Note that I am assuming an unidentified person is a "new" person. I suspect that
There are two types of `Relationships`: `ToOneRelationship` and `ToManyRelationship`. An `EntityDescription`'s `Relationships` type can contain any number of `Relationship` properties of either of these types. Do not store anything other than `Relationship` properties in the `Relationships` struct of an `EntityDescription`.
To describe a relationship that may be omitted (i.e. the key is not even present in the JSON object), you make the entire `ToOneRelationship` or `ToManyRelationship` optional. However, this is not recommended because you can also represent optional relationships as nullable which means the key is always present. A `ToManyRelationship` can naturally represent the absence of related values with an empty array, so `ToManyRelationship` does not support nullability at all. A `ToOneRelationship` can be marked as nullable (i.e. the value might be `null` or it might be a resource identifier) like this:
In addition to identifying entities by Id and type, `Relationships` can contain `Meta` or `Links` that follow the same rules as [`Meta`](#jsonapimeta) and [`Links`](#jsonapilinks) elsewhere in the JSON API Document.
To describe a relationship that may be omitted (i.e. the key is not even present in the JSON object), you make the entire `ToOneRelationship` or `ToManyRelationship` optional. However, this is not recommended because you can also represent optional relationships as nullable which means the key is always present. A `ToManyRelationship` can naturally represent the absence of related values with an empty array, so `ToManyRelationship` does not support nullability at all. A `ToOneRelationship` can be marked as nullable (i.e. the value could be either `null` or a resource identifier) like this:
```
let nullableRelative: ToOneRelationship<Person?>
let nullableRelative: ToOneRelationship<Person?, NoMetadata, NoLinks>
```
An entity that does not have relationships can be described by adding the following to an `EntityDescription`: