IsKey

Not available in this language yet.
IsKey( value )
IsKey( value )
IsKey( value )
Not available in this language yet.
IsKey( value )

Description

The IsKey function returns true only if value is a key, otherwise it returns false.

Parameters

Argument Type Definition and Requirements

value

Any

Any value, which is to be tested to determine whether it is a key or not.

Returns

Returns a boolean, indicating whether value was a key or not.

Examples

The following query uses Map to iterate over an array of all of the types of values that can be tested by a type-check function, passing each item into a Lambda function that returns an object, which contains the value and the result of calling IsKey with that value:

Not available in this language yet.
result, err := client.Query(
  f.Map(
    f.Arr{
      f.Arr{"array"},
      true,
      false,
      f.BytesV{0x01, 0x02, 0x03, 0x04},
      f.Arr{0x1, 0x2, 0x3, 0x4},
      f.Collection("Letters"),
      f.Ref("credentials/self"),
      f.Database("child_db"),
      f.Date("2019-11-12"),
      f.RefCollection(f.Collection("Letters"), 123),
      10.1,
      f.Function("double"),
      f.Index("all_letters"),
      10,
      f.RefCollection(f.Keys(), "248967241620521472"),
      f.Query(f.Lambda("x", f.Var("x"))),
      nil,
      f.Null(),
      f.Obj{ "x": 10 },
      f.Role("employees"),
      f.Match(f.Index("all_letters")),
      "ten",
      "10",
      f.Now(),
      f.RefCollection(f.Tokens(), "249062079147803136"),
    },
    f.Lambda("x", f.Obj{
      "value": f.Var("x"),
      "IsKey": f.IsKey(f.Var("x")),
    })))

if (err != nil) {
  fmt.Println(err)
} else {
  fmt.Println(result)
}
[map[IsKey:false value:[array]] map[IsKey:false value:true] map[IsKey:false value:false] map[IsKey:false value:[1 2 3 4]] map[IsKey:false value:[1 2 3 4]] map[IsKey:false value:{Letters 0xc00021e1b0 0xc00021e1b0 <nil>}] map[IsKey:false value:{264354436692836874 0xc00021e2d0 0xc00021e2d0 <nil>}] map[IsKey:false value:{child_db 0xc00021e3f0 0xc00021e3f0 <nil>}] map[IsKey:false value:{0 63709113600 <nil>}] map[IsKey:false value:{123 0xc00021e600 0xc00021e600 <nil>}] map[IsKey:false value:10.1] map[IsKey:false value:{double 0xc00021e750 0xc00021e750 <nil>}] map[IsKey:false value:{all_letters 0xc00021e870 0xc00021e870 <nil>}] map[IsKey:false value:10] map[IsKey:true value:{248967241620521472 0xc00021e9c0 0xc00021e9c0 <nil>}] map[IsKey:false value:{[123 34 108 97 109 98 100 97 34 58 34 120 34 44 34 101 120 112 114 34 58 123 34 118 97 114 34 58 34 120 34 125 125]}] map[IsKey:false value:{}] map[IsKey:false value:{}] map[IsKey:false value:map[x:10]] map[IsKey:false value:{employees 0xc00021ebd0 0xc00021ebd0 <nil>}] map[IsKey:false value:{map[match:{all_letters 0xc00021ed20 0xc00021ed20 <nil>}]}] map[IsKey:false value:ten] map[IsKey:false value:10] map[IsKey:false value:{760575000 63724302444 <nil>}] map[IsKey:false value:{249062079147803136 0xc00021eed0 0xc00021eed0 <nil>}]]
System.out.println(
    client.query(
        Map(
            Arr(
                Arr(Value("array")),
                Value(true),
                Value(false),
                Value(new byte[] {0x1, 0x2, 0x3, 0x4}),
                Arr(Value(0x1), Value(0x2), Value(0x3), Value(0x4)),
                Collection("Letters"),
                Ref("credentials/self"),
                Database("child_db"),
                Date("2019-11-12"),
                Ref(Collection("Letters"), "123"),
                Value(10.1),
                Function("double"),
                Index("all_letters"),
                Value(10),
                Ref(Keys(), "248967241620521472"),
                Query(Lambda("x", Var("x"))),
                Null(),
                Obj("x", Value(10)),
                Role("employees"),
                Match(Index("all_letters")),
                Value("ten"),
                Value("10"),
                Now(),
                Ref(Tokens(), "249062079147803136")
            ),
            Lambda(
                "x",
                Obj("value", Var("x"), "IsKey", IsKey(Var("x")))
            )
        )
    ).get());
[{value: ["array"], IsKey: false},
 {value: true, IsKey: false},
 {value: false, IsKey: false},
 {value: [0x01 0x02 0x03 0x04], IsKey: false},
 {value: [1, 2, 3, 4], IsKey: false},
 {value: ref(id = "Letters", collection = ref(id = "collections")),
  IsKey: false},
 {value: ref(id = "248967019900174848", collection = ref(id = "credentials")),
  IsKey: false},
 {value: ref(id = "child_db", collection = ref(id = "databases")),
  IsKey: false},
 {value: 2019-11-12, IsKey: false},
 {value: ref(id = "123", collection = ref(id = "Letters", collection = ref(id = "collections"))),
  IsKey: false},
 {value: 10.1, IsKey: false},
 {value: ref(id = "double", collection = ref(id = "functions")),
  IsKey: false},
 {value: ref(id = "all_letters", collection = ref(id = "indexes")),
  IsKey: false},
 {value: 10, IsKey: false},
 {value: ref(id = "248967241620521472", collection = ref(id = "keys")),
  IsKey: true},
 {value: QueryV({lambda=x, expr={var=x}}), IsKey: false},
 {value: null, IsKey: false},
 {value: {x: 10}, IsKey: false},
 {value: ref(id = "employees", collection = ref(id = "roles")),
  IsKey: false},
 {value: {@set = {match: ref(id = "all_letters", collection = ref(id = "indexes"))}},
  IsKey: false},
 {value: "ten", IsKey: false},
 {value: "10", IsKey: false},
 {value: 2019-11-12T13:15:16.789Z, IsKey: false},
 {value: ref(id = "249062079147803136", collection = ref(id = "tokens")),
  IsKey: false}]
client.query(
  q.Map(
    [
      ['array'],
      true,
      false,
      new Uint8Array([1, 2, 3, 4]),
      [0x1, 0x2, 0x3, 0x4],
      q.Collection('Letters'),
      q.Ref('credentials/self'),
      q.Database('child_db'),
      q.Date('2019-11-12'),
      q.Ref(q.Collection('Letters'), 123),
      10.1,
      q.Function('double'),
      q.Index('all_letters'),
      10,
      q.Ref(q.Keys(), '248967241620521472'),
      q.Query(q.Lambda('x', q.Var('x'))),
      null,
      { x: 10 },
      q.Role('employees'),
      q.Match(q.Index('all_letters')),
      'ten',
      '10',
      q.Now(),
      q.Ref(q.Tokens(), '249062079147803136'),
    ],
    q.Lambda('x', {
      value: q.Var('x'),
      IsKey: q.IsKey(q.Var('x')),
    })
  )
)
.then((ret) => console.log(ret))
[ { value: [ 'array' ], IsKey: false },
  { value: true, IsKey: false },
  { value: false, IsKey: false },
  { value: Bytes("AQIDBA=="), IsKey: false },
  { value: [ 1, 2, 3, 4 ], IsKey: false },
  { value: Collection("Letters"), IsKey: false },
  { value: Ref(Credentials(), "248967019900174848"),
    IsKey: false },
  { value: Database("child_db"), IsKey: false },
  { value: Date("2019-11-12"), IsKey: false },
  { value: Ref(Collection("Letters"), "123"), IsKey: false },
  { value: 10.1, IsKey: false },
  { value: Function("double"), IsKey: false },
  { value: Index("all_letters"), IsKey: false },
  { value: 10, IsKey: false },
  { value: Ref(Keys(), "248967241620521472"), IsKey: true },
  { value: Query(Lambda("x", Var("x"))), IsKey: false },
  { value: null, IsKey: false },
  { value: { x: 10 }, IsKey: false },
  { value: Role("employees"), IsKey: false },
  { value: Match(Index("all_letters")), IsKey: false },
  { value: 'ten', IsKey: false },
  { value: '10', IsKey: false },
  { value: Time("2019-11-12T13:15:16.789Z"), IsKey: false },
  { value: Ref(Tokens(), "249062079147803136"), IsKey: false } ]
Not available in this language yet.
println(Await.result(
  client.query(
    Map(
      Arr(
        Arr("array"),
        true,
        false,
        BytesV(0x1, 0x2, 0x3, 0x4),
        Arr(0x1, 0x2, 0x3, 0x4),
        Collection("Letters"),
        Ref("credentials/self"),
        Database("child_db"),
        Date("2019-11-12"),
        Ref(Collection("Letters"), 123),
        10.1,
        Function("double"),
        Index("all_letters"),
        10,
        Ref(Keys(), "248967241620521472"),
        Query(Lambda("x", Var("x"))),
        Null,
        Obj("x" -> 10),
        Role("employees"),
        Match(Index("all_letters")),
        "ten",
        "10",
        Now(),
        Ref(Tokens(), "249062079147803136")
      ),
      Lambda(
        "x",
        Obj( "value" -> Var("x"), "IsKey" -> IsKey(Var("x")))
      )
    )
  ),
  5.seconds
))
[{value: ["array"], IsKey: false},
 {value: true, IsKey: false},
 {value: false, IsKey: false},
 {value: [0x01 0x02 0x03 0x04], IsKey: false},
 {value: [1, 2, 3, 4], IsKey: false},
 {value: ref(id = "Letters", collection = ref(id = "collections")),
  IsKey: false},
 {value: ref(id = "248967019900174848", collection = ref(id = "credentials")),
  IsKey: false},
 {value: ref(id = "child_db", collection = ref(id = "databases")),
  IsKey: false},
 {value: 2019-11-12, IsKey: false},
 {value: ref(id = "123", collection = ref(id = "Letters", collection = ref(id = "collections"))),
  IsKey: false},
 {value: 10.1, IsKey: false},
 {value: ref(id = "double", collection = ref(id = "functions")),
  IsKey: false},
 {value: ref(id = "all_letters", collection = ref(id = "indexes")),
  IsKey: false},
 {value: 10, IsKey: false},
 {value: ref(id = "248967241620521472", collection = ref(id = "keys")),
  IsKey: true},
 {value: {lambda: "x", expr: {var: "x"}}, IsKey: false},
 {value: NullV, IsKey: false},
 {value: {x: 10}, IsKey: false},
 {value: ref(id = "employees", collection = ref(id = "roles")),
  IsKey: false},
 {value: {@set = {match: ref(id = "all_letters", collection = ref(id = "indexes"))}},
  IsKey: false},
 {value: "ten", IsKey: false},
 {value: "10", IsKey: false},
 {value: 2019-11-12T13:15:16.789Z, IsKey: false},
 {value: ref(id = "249062079147803136", collection = ref(id = "tokens")),
  IsKey: false}]

This query operates on a pre-existing schema, which is not provided here.

Also, the query is executed via a client connection, that uses a secret acquired by calling Login (not shown here), so that Ref("credentials/self") returns a valid value.

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