Check out v4 of the Fauna CLI

v4 of the Fauna CLI is now in beta.

The new version introduces enhancements to the developer experience, including an improved authentication workflow. To get started, check out the CLI v4 quick start.

Set.single()

Create a Set containing a single provided element.

Signature

Set.single(element: A) => Set<A>

Description

Creates a Set containing a single element. The element is passed to the method as an argument.

You can use an event source to track changes to a Set containing a single document. These event sources only emit events when the document changes.

You typically use Set.single() to create a Set from a Document for a document event source.

Parameters

Parameter Type Required Description

element

Generic

Yes

Value for the returned Set's element.

Return value

Type Description

Set<Generic>

Set containing the provided element.

Examples

The following uses single() to creates a Set from a single document.

// Uses the `Product` collection's `byName()` index and
// the `first()` method to get a single document.
let product = Product.byName("cups").first()
Set.single(product)
{
  data: [
    {
      id: "111",
      coll: Product,
      ts: Time("2099-03-21T19:40:45.430Z"),
      name: "cups",
      description: "Translucent 9 Oz, 100 ct",
      price: 698,
      stock: 100,
      category: Category("123")
    }
  ]
}

You can call set.eventsOn() or set.eventSource() on the Set to create a document event sources.

let product = Product.byName("cups").first()
Set.single(product).eventSource()

The query returns an event source:

"g9WD1YPG..."

Is this article helpful? 

Tell Fauna how the article can be improved:
 Visit Fauna's forums or email docs@fauna.com

Thank you for your feedback!