`Key.firstWhere()`

Get the first key matching a provided predicate.

Signature

Key.firstWhere(pred: (Key => Boolean)) => Key | Null

Description

Gets the first Key document that matches a provided predicate function.

Parameters

Parameter Type Required Description

Parameter	Type	Required	Description
pred	Predicate function	Yes	Anonymous predicate function that: Accepts a `Key` document as its only argument. Supports shorthand-syntax. Returns a Boolean value. The method returns the first `Key` document for which the predicate returns true.

pred

Predicate function

Yes

Anonymous predicate function that:

Accepts a Key document as its only argument. Supports shorthand-syntax.
Returns a Boolean value.

The method returns the first Key document for which the predicate returns true.

Return value

One of:

Type Description

Type	Description
Key	First `Key` document that matches the predicate.
Null	No `Key` document matches the predicate.

Key

First Key document that matches the predicate.

Null

No Key document matches the predicate.

Examples

Key.firstWhere(.role == "admin")

{
  id: "412655134325080576",
  coll: Key,
  ts: Time("2099-07-19T20:53:15.250Z"),
  role: "admin",
  data: {
    desc: "Admin key for prod app database"
  }
}

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