IsArray

This reference topic applies to FQL v4. Go to this page for the latest FQL v10 reference topics.

IsArray( value )
IsArray( value )
IsArray( value )
is_array( value )
IsArray( value )

Description

The IsArray function returns true only if value is an Array, otherwise it returns false.

Parameters

Parameter Type Definition and Requirements

value

Any

Any value, which is to be tested to determine whether it is an Array or not.

Returns

Returns a Boolean, indicating whether value was an Array 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 IsArray with that value:

try
{
    Value result = await client.Query(
        Map(
            Arr(
                Arr("array"),
                true,
                false,
                BytesV.Of(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("letters"),
                10,
                Ref(Keys(), "1"),
                Query(Lambda("x", Var("x"))),
                null,
                Obj("x", 10),
                Role("employees"),
                Match(Index("letters")),
                "ten",
                "10",
                Time("2020-07-06T12:34:56.789Z"),
                Ref(Tokens(), "1")
            ),
            Lambda(
                "x",
                Obj(
                    "value", Var("x"),
                    "IsArray", IsArray(Var("x"))
                )
            )
        )
    );

    Console.WriteLine(result);
}
catch (Exception e)
{
    Console.WriteLine($"ERROR: {e.Message}");
}
Arr(ObjectV(value: Arr(StringV(array)),IsArray: BooleanV(True)), ObjectV(value: BooleanV(True),IsArray: BooleanV(False)), ObjectV(value: BooleanV(False),IsArray: BooleanV(False)), ObjectV(value: BytesV(0x01, 0x02, 0x03, 0x04),IsArray: BooleanV(False)), ObjectV(value: Arr(LongV(1), LongV(2), LongV(3), LongV(4)),IsArray: BooleanV(True)), ObjectV(value: RefV(id = "Letters", collection = RefV(id = "collections")),IsArray: BooleanV(False)), ObjectV(value: RefV(id = "295434789658296832", collection = RefV(id = "credentials")),IsArray: BooleanV(False)), ObjectV(value: RefV(id = "child_db", collection = RefV(id = "databases")),IsArray: BooleanV(False)), ObjectV(value: FaunaDate(2019-11-12 12:00:00 AM),IsArray: BooleanV(False)), ObjectV(value: RefV(id = "123", collection = RefV(id = "Letters", collection = RefV(id = "collections"))),IsArray: BooleanV(False)), ObjectV(value: DoubleV(10.1),IsArray: BooleanV(False)), ObjectV(value: RefV(id = "double", collection = RefV(id = "functions")),IsArray: BooleanV(False)), ObjectV(value: RefV(id = "letters", collection = RefV(id = "indexes")),IsArray: BooleanV(False)), ObjectV(value: LongV(10),IsArray: BooleanV(False)), ObjectV(value: RefV(id = "1", collection = RefV(id = "keys")),IsArray: BooleanV(False)), ObjectV(value: QueryV(System.Collections.Generic.Dictionary`2[System.String,FaunaDB.Query.Expr]),IsArray: BooleanV(False)), ObjectV(value: NullV,IsArray: BooleanV(False)), ObjectV(value: ObjectV(x: LongV(10)),IsArray: BooleanV(False)), ObjectV(value: RefV(id = "employees", collection = RefV(id = "roles")),IsArray: BooleanV(False)), ObjectV(value: SetRefV(System.Collections.Generic.Dictionary`2[System.String,FaunaDB.Types.Value]),IsArray: BooleanV(False)), ObjectV(value: StringV(ten),IsArray: BooleanV(False)), ObjectV(value: StringV(10),IsArray: BooleanV(False)), ObjectV(value: FaunaTime(2020-07-06T12:34:56.789Z),IsArray: BooleanV(False)), ObjectV(value: RefV(id = "1", collection = RefV(id = "tokens")),IsArray: BooleanV(False)))
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.Ref(f.Collection("Letters"), 123),
			10.1,
			f.Function("double"),
			f.Index("letters"),
			10,
			f.Ref(f.Keys(), "1"),
			f.Query(f.Lambda("x", f.Var("x"))),
			nil,
			f.Null(),
			f.Obj{"x": 10},
			f.Role("employees"),
			f.Documents(f.Collection("Letters")),
			"ten",
			"10",
			f.Time("2020-07-06T12:34:56.789Z"),
			f.Ref(f.Tokens(), "1"),
		},
		f.Lambda("x", f.Obj{
			"value": f.Var("x"),
			"IsArray": f.IsArray(f.Var("x")),
		})))

if err != nil {
	fmt.Fprintln(os.Stderr, err)
} else {
	fmt.Println(result)
}
[map[IsArray:true value:[array]] map[IsArray:false value:true] map[IsArray:false value:false] map[IsArray:false value:[1 2 3 4]] map[IsArray:true value:[1 2 3 4]] map[IsArray:false value:{Letters 0xc000148210 0xc000148210 <nil>}] map[IsArray:false value:{280481857410171392 0xc000148330 0xc000148330 <nil>}] map[IsArray:false value:{child_db 0xc000148450 0xc000148450 <nil>}] map[IsArray:false value:{0 63709113600 <nil>}] map[IsArray:false value:{123 0xc00018c150 0xc00018c150 <nil>}] map[IsArray:false value:10.1] map[IsArray:false value:{double 0xc00018c2a0 0xc00018c2a0 <nil>}] map[IsArray:false value:{letters 0xc00018c3c0 0xc00018c3c0 <nil>}] map[IsArray:false value:10] map[IsArray:false value:{1 0xc00018c510 0xc00018c510 <nil>}] map[IsArray:false value:{[123 34 97 112 105 95 118 101 114 115 105 111 110 34 58 34 51 34 44 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[IsArray:false value:{}] map[IsArray:false value:{}] map[IsArray:false value:map[x:10]] map[IsArray:false value:{employees 0xc00018c720 0xc00018c720 <nil>}] map[IsArray:false value:{map[documents:{Letters 0xc00018c870 0xc00018c870 <nil>}]}] map[IsArray:false value:ten] map[IsArray:false value:10] map[IsArray:false value:{789000000 63729635696 <nil>}] map[IsArray:false value:{1 0xc00018ca20 0xc00018ca20 <nil>}]]
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('letters'),
      10,
      q.Ref(q.Keys(), '1'),
      q.Query(q.Lambda('x', q.Var('x'))),
      null,
      { x: 10 },
      q.Role('employees'),
      q.Match(q.Index('letters')),
      'ten',
      '10',
      q.Time('2020-07-06T12:34:56.789Z'),
      q.Ref(q.Tokens(), '1'),
    ],
    q.Lambda('x', {
      value: q.Var('x'),
      IsArray: q.IsArray(q.Var('x')),
    })
  )
)
.then((ret) => console.log(ret))
.catch((err) => console.error(
  'Error: [%s] %s: %s',
  err.name,
  err.message,
  err.errors()[0].description,
))
[
  { value: [ 'array' ], IsArray: true },
  { value: true, IsArray: false },
  { value: false, IsArray: false },
  { value: Bytes("AQIDBA=="), IsArray: false },
  { value: [ 1, 2, 3, 4 ], IsArray: true },
  { value: Collection("Letters"), IsArray: false },
  { value: Ref(Credentials(), "268287530751754752"), IsArray: false },
  { value: Database("child_db"), IsArray: false },
  { value: Date("2019-11-12"), IsArray: false },
  { value: Ref(Collection("Letters"), "123"), IsArray: false },
  { value: 10.1, IsArray: false },
  { value: Function("double"), IsArray: false },
  { value: Index("letters"), IsArray: false },
  { value: 10, IsArray: false },
  { value: Ref(Keys(), "1"), IsArray: false },
  { value: Query(Lambda("x", Var("x"))), IsArray: false },
  { value: null, IsArray: false },
  { value: { x: 10 }, IsArray: false },
  { value: Role("employees"), IsArray: false },
  { value: Match(Index("letters")), IsArray: false },
  { value: 'ten', IsArray: false },
  { value: '10', IsArray: false },
  { value: Time("2020-06-14T06:56:18.539Z"), IsArray: false },
  { value: Ref(Tokens(), "1"), IsArray: false }
]
result = client.query(
  q.map_(
    q.lambda_("x", {
      "value": q.var("x"),
      "IsArray": q.is_array(q.var("x")),
    }),
    [
      ["array"],
      True,
      False,
      bytearray([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("letters"),
      10,
      q.ref(q.keys(), "1"),
      q.query(q.lambda_("x", q.var("x"))),
      None,
      {"x": 10},
      q.role("employees"),
      q.match(q.index("letters")),
      "ten",
      "10",
      q.time("2020-07-06T12:34:56.789Z"),
      q.ref(q.tokens(), "1"),
    ],
  )
)
print(result)
[{'value': ['array'], 'IsArray': True}, {'value': True, 'IsArray': False}, {'value': False, 'IsArray': False}, {'value': bytearray(b'\x01\x02\x03\x04'), 'IsArray': False}, {'value': [1, 2, 3, 4], 'IsArray': True}, {'value': Ref(id=Letters, collection=Ref(id=collections)), 'IsArray': False}, {'value': Ref(id=282032258185953792, collection=Ref(id=credentials)), 'IsArray': False}, {'value': Ref(id=child_db, collection=Ref(id=databases)), 'IsArray': False}, {'value': datetime.date(2019, 11, 12), 'IsArray': False}, {'value': Ref(id=123, collection=Ref(id=Letters, collection=Ref(id=collections))), 'IsArray': False}, {'value': 10.1, 'IsArray': False}, {'value': Ref(id=double, collection=Ref(id=functions)), 'IsArray': False}, {'value': Ref(id=letters, collection=Ref(id=indexes)), 'IsArray': False}, {'value': 10, 'IsArray': False}, {'value': Ref(id=1, collection=Ref(id=keys)), 'IsArray': False}, {'value': Query({'api_version': '4', 'lambda': 'x', 'expr': {'var': 'x'}}), 'IsArray': False}, {'value': None, 'IsArray': False}, {'value': {'x': 10}, 'IsArray': False}, {'value': Ref(id=employees, collection=Ref(id=roles)), 'IsArray': False}, {'value': SetRef({'match': Ref(id=letters, collection=Ref(id=indexes))}), 'IsArray': False}, {'value': 'ten', 'IsArray': False}, {'value': '10', 'IsArray': False}, {'value': FaunaTime('2020-07-06T12:34:56.789Z'), 'IsArray': False}, {'value': Ref(id=1, collection=Ref(id=tokens)), 'IsArray': False}]
Map(
  [
    ['array'],
    true,
    false,
    new Uint8Array([1, 2, 3, 4]),
    [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('letters'),
    10,
    Ref(Keys(), '1'),
    Query(Lambda('x', Var('x'))),
    null,
    { x: 10 },
    Role('employees'),
    Match(Index('letters')),
    'ten',
    '10',
    Time('2020-07-06T12:34:56.789Z'),
    Ref(Tokens(), '1'),
  ],
  Lambda('x', {
    value: Var('x'),
    IsArray: IsArray(Var('x')),
  })
)
[
  { value: [ 'array' ], IsArray: true },
  { value: true, IsArray: false },
  { value: false, IsArray: false },
  { value: { '0': 1, '1': 2, '2': 3, '3': 4 }, IsArray: false },
  { value: [ 1, 2, 3, 4 ], IsArray: true },
  { value: Collection("Letters"), IsArray: false },
  { value: Ref(Credentials(), "302043979982045696"), IsArray: false },
  { value: Database("child_db"), IsArray: false },
  { value: Date("2019-11-12"), IsArray: false },
  { value: Ref(Collection("Letters"), "123"), IsArray: false },
  { value: 10.1, IsArray: false },
  { value: Function("double"), IsArray: false },
  { value: Index("letters"), IsArray: false },
  { value: 10, IsArray: false },
  { value: Ref(Keys(), "1"), IsArray: false },
  { value: Query(Lambda("x", Var("x"))), IsArray: false },
  { value: null, IsArray: false },
  { value: { x: 10 }, IsArray: false },
  { value: Role("employees"), IsArray: false },
  { value: Match(Index("letters")), IsArray: false },
  { value: 'ten', IsArray: false },
  { value: '10', IsArray: false },
  { value: Time("2020-07-06T12:34:56.789Z"), IsArray: false },
  { value: Ref(Tokens(), "1"), IsArray: false }
]
Query metrics:
  •    bytesIn:   598

  •   bytesOut: 1,558

  • computeOps:     2

  •    readOps:     0

  •   writeOps:     0

  •  readBytes:   373

  • writeBytes:     0

  •  queryTime:  79ms

  •    retries:     0

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 the Login function (not shown here), so that Ref("credentials/self") returns a valid value.

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