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`IsNumber`

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

IsNumber( value )

is_number( value )

IsNumber( value )

IsNumber( value )

IsNumber( value )

Description

The IsNumber function tests the provided value and returns true only if value is a number (floating point, or integer), otherwise it returns false.

Parameters

Parameter Type Definition and Requirements

Parameter	Type	Definition and Requirements
`value`	Any	Any value, which is to be tested to determine whether it is a Number or not.

value

Any

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

Returns

Returns a Boolean, indicating whether value was a Number 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 IsNumber with that value:

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'),
      IsNumber: q.IsNumber(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' ], IsNumber: false },
  { value: true, IsNumber: false },
  { value: false, IsNumber: false },
  { value: Bytes("AQIDBA=="), IsNumber: false },
  { value: [ 1, 2, 3, 4 ], IsNumber: false },
  { value: Collection("Letters"), IsNumber: false },
  { value: Ref(Credentials(), "268432796604695040"), IsNumber: false },
  { value: Database("child_db"), IsNumber: false },
  { value: Date("2019-11-12"), IsNumber: false },
  { value: Ref(Collection("Letters"), "123"), IsNumber: false },
  { value: 10.1, IsNumber: true },
  { value: Function("double"), IsNumber: false },
  { value: Index("letters"), IsNumber: false },
  { value: 10, IsNumber: true },
  { value: Ref(Keys(), "1"), IsNumber: false },
  { value: Query(Lambda("x", Var("x"))), IsNumber: false },
  { value: null, IsNumber: false },
  { value: { x: 10 }, IsNumber: false },
  { value: Role("employees"), IsNumber: false },
  { value: Match(Index("letters")), IsNumber: false },
  { value: 'ten', IsNumber: false },
  { value: '10', IsNumber: false },
  { value: Time("2020-06-15T21:25:14.961Z"), IsNumber: false },
  { value: Ref(Tokens(), "1"), IsNumber: false }
]

result = client.query(
  q.map_(
    q.lambda_("x", {
      "value": q.var("x"),
      "IsNumber": q.is_number(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'], 'IsNumber': False}, {'value': True, 'IsNumber': False}, {'value': False, 'IsNumber': False}, {'value': bytearray(b'\x01\x02\x03\x04'), 'IsNumber': False}, {'value': [1, 2, 3, 4], 'IsNumber': False}, {'value': Ref(id=Letters, collection=Ref(id=collections)), 'IsNumber': False}, {'value': Ref(id=282032258185953792, collection=Ref(id=credentials)), 'IsNumber': False}, {'value': Ref(id=child_db, collection=Ref(id=databases)), 'IsNumber': False}, {'value': datetime.date(2019, 11, 12), 'IsNumber': False}, {'value': Ref(id=123, collection=Ref(id=Letters, collection=Ref(id=collections))), 'IsNumber': False}, {'value': 10.1, 'IsNumber': True}, {'value': Ref(id=double, collection=Ref(id=functions)), 'IsNumber': False}, {'value': Ref(id=letters, collection=Ref(id=indexes)), 'IsNumber': False}, {'value': 10, 'IsNumber': True}, {'value': Ref(id=1, collection=Ref(id=keys)), 'IsNumber': False}, {'value': Query({'api_version': '4', 'lambda': 'x', 'expr': {'var': 'x'}}), 'IsNumber': False}, {'value': None, 'IsNumber': False}, {'value': {'x': 10}, 'IsNumber': False}, {'value': Ref(id=employees, collection=Ref(id=roles)), 'IsNumber': False}, {'value': SetRef({'match': Ref(id=letters, collection=Ref(id=indexes))}), 'IsNumber': False}, {'value': 'ten', 'IsNumber': False}, {'value': '10', 'IsNumber': False}, {'value': FaunaTime('2020-07-06T12:34:56.789Z'), 'IsNumber': False}, {'value': Ref(id=1, collection=Ref(id=tokens)), 'IsNumber': 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.Match(f.Index("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"),
			"IsNumber": f.IsNumber(f.Var("x")),
		})))

if err != nil {
	fmt.Fprintln(os.Stderr, err)
} else {
	fmt.Println(result)
}

[map[IsNumber:false value:[array]] map[IsNumber:false value:true] map[IsNumber:false value:false] map[IsNumber:false value:[1 2 3 4]] map[IsNumber:false value:[1 2 3 4]] map[IsNumber:false value:{Letters 0xc000126210 0xc000126210 <nil>}] map[IsNumber:false value:{280481857410171392 0xc000126330 0xc000126330 <nil>}] map[IsNumber:false value:{child_db 0xc000126450 0xc000126450 <nil>}] map[IsNumber:false value:{0 63709113600 <nil>}] map[IsNumber:false value:{123 0xc000126720 0xc000126720 <nil>}] map[IsNumber:true value:10.1] map[IsNumber:false value:{double 0xc000126870 0xc000126870 <nil>}] map[IsNumber:false value:{letters 0xc000126990 0xc000126990 <nil>}] map[IsNumber:true value:10] map[IsNumber:false value:{1 0xc000126ae0 0xc000126ae0 <nil>}] map[IsNumber: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[IsNumber:false value:{}] map[IsNumber:false value:{}] map[IsNumber:false value:map[x:10]] map[IsNumber:false value:{employees 0xc000126cf0 0xc000126cf0 <nil>}] map[IsNumber:false value:{map[match:{letters 0xc000126e40 0xc000126e40 <nil>}]}] map[IsNumber:false value:ten] map[IsNumber:false value:10] map[IsNumber:false value:{789000000 63729635696 <nil>}] map[IsNumber:false value:{1 0xc000126ff0 0xc000126ff0 <nil>}]]

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"),
                    "IsNumber", IsNumber(Var("x"))
                )
            )
        )
    );

    Console.WriteLine(result);
}
catch (Exception e)
{
    Console.WriteLine($"ERROR: {e.Message}");
}

Arr(ObjectV(value: Arr(StringV(array)),IsNumber: BooleanV(False)), ObjectV(value: BooleanV(True),IsNumber: BooleanV(False)), ObjectV(value: BooleanV(False),IsNumber: BooleanV(False)), ObjectV(value: BytesV(0x01, 0x02, 0x03, 0x04),IsNumber: BooleanV(False)), ObjectV(value: Arr(LongV(1), LongV(2), LongV(3), LongV(4)),IsNumber: BooleanV(False)), ObjectV(value: RefV(id = "Letters", collection = RefV(id = "collections")),IsNumber: BooleanV(False)), ObjectV(value: RefV(id = "295432693043167744", collection = RefV(id = "credentials")),IsNumber: BooleanV(False)), ObjectV(value: RefV(id = "child_db", collection = RefV(id = "databases")),IsNumber: BooleanV(False)), ObjectV(value: FaunaDate(2019-11-12 12:00:00 AM),IsNumber: BooleanV(False)), ObjectV(value: RefV(id = "123", collection = RefV(id = "Letters", collection = RefV(id = "collections"))),IsNumber: BooleanV(False)), ObjectV(value: DoubleV(10.1),IsNumber: BooleanV(True)), ObjectV(value: RefV(id = "double", collection = RefV(id = "functions")),IsNumber: BooleanV(False)), ObjectV(value: RefV(id = "letters", collection = RefV(id = "indexes")),IsNumber: BooleanV(False)), ObjectV(value: LongV(10),IsNumber: BooleanV(True)), ObjectV(value: RefV(id = "1", collection = RefV(id = "keys")),IsNumber: BooleanV(False)), ObjectV(value: QueryV(System.Collections.Generic.Dictionary`2[System.String,FaunaDB.Query.Expr]),IsNumber: BooleanV(False)), ObjectV(value: NullV,IsNumber: BooleanV(False)), ObjectV(value: ObjectV(x: LongV(10)),IsNumber: BooleanV(False)), ObjectV(value: RefV(id = "employees", collection = RefV(id = "roles")),IsNumber: BooleanV(False)), ObjectV(value: SetRefV(System.Collections.Generic.Dictionary`2[System.String,FaunaDB.Types.Value]),IsNumber: BooleanV(False)), ObjectV(value: StringV(ten),IsNumber: BooleanV(False)), ObjectV(value: StringV(10),IsNumber: BooleanV(False)), ObjectV(value: FaunaTime(2020-07-06T12:34:56.789Z),IsNumber: BooleanV(False)), ObjectV(value: RefV(id = "1", collection = RefV(id = "tokens")),IsNumber: BooleanV(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'),
    IsNumber: IsNumber(Var('x')),
  })
)

[
  { value: [ 'array' ], IsNumber: false },
  { value: true, IsNumber: false },
  { value: false, IsNumber: false },
  { value: { '0': 1, '1': 2, '2': 3, '3': 4 }, IsNumber: false },
  { value: [ 1, 2, 3, 4 ], IsNumber: false },
  { value: Collection("Letters"), IsNumber: false },
  { value: Ref(Credentials(), "302043979982045696"), IsNumber: false },
  { value: Database("child_db"), IsNumber: false },
  { value: Date("2019-11-12"), IsNumber: false },
  { value: Ref(Collection("Letters"), "123"), IsNumber: false },
  { value: 10.1, IsNumber: true },
  { value: Function("double"), IsNumber: false },
  { value: Index("letters"), IsNumber: false },
  { value: 10, IsNumber: true },
  { value: Ref(Keys(), "1"), IsNumber: false },
  { value: Query(Lambda("x", Var("x"))), IsNumber: false },
  { value: null, IsNumber: false },
  { value: { x: 10 }, IsNumber: false },
  { value: Role("employees"), IsNumber: false },
  { value: Match(Index("letters")), IsNumber: false },
  { value: 'ten', IsNumber: false },
  { value: '10', IsNumber: false },
  { value: Time("2020-07-06T12:34:56.789Z"), IsNumber: false },
  { value: Ref(Tokens(), "1"), IsNumber: false }
]

Query metrics:

bytesIn: 600
bytesOut: 1,582
computeOps: 2
readOps: 0
writeOps: 0
readBytes: 373
writeBytes: 0
queryTime: 24ms
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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IsNumber

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Returns

Examples

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`IsNumber`