IsBoolean

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

Description

The IsBoolean function returns true only if value is a Boolean, 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 boolean or not.

Returns

Returns a boolean, indicating whether value was a boolean 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 IsBoolean 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"),
      "IsBoolean": f.IsBoolean(f.Var("x")),
    })))

if (err != nil) {
  fmt.Println(err)
} else {
  fmt.Println(result)
}
[map[IsBoolean:false value:[array]] map[IsBoolean:true value:true] map[IsBoolean:true value:false] map[IsBoolean:false value:[1 2 3 4]] map[IsBoolean:false value:[1 2 3 4]] map[IsBoolean:false value:{Letters 0xc00008e4b0 0xc00008e4b0 <nil>}] map[IsBoolean:false value:{264354436692836874 0xc00008e5d0 0xc00008e5d0 <nil>}] map[IsBoolean:false value:{child_db 0xc00008e6f0 0xc00008e6f0 <nil>}] map[IsBoolean:false value:{0 63709113600 <nil>}] map[IsBoolean:false value:{123 0xc00008e900 0xc00008e900 <nil>}] map[IsBoolean:false value:10.1] map[IsBoolean:false value:{double 0xc00008ea50 0xc00008ea50 <nil>}] map[IsBoolean:false value:{all_letters 0xc00008eb70 0xc00008eb70 <nil>}] map[IsBoolean:false value:10] map[IsBoolean:false value:{248967241620521472 0xc00008ecc0 0xc00008ecc0 <nil>}] map[IsBoolean: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[IsBoolean:false value:{}] map[IsBoolean:false value:{}] map[IsBoolean:false value:map[x:10]] map[IsBoolean:false value:{employees 0xc00008eed0 0xc00008eed0 <nil>}] map[IsBoolean:false value:{map[match:{all_letters 0xc00008f020 0xc00008f020 <nil>}]}] map[IsBoolean:false value:ten] map[IsBoolean:false value:10] map[IsBoolean:false value:{937020000 63724302108 <nil>}] map[IsBoolean:false value:{249062079147803136 0xc00008f1d0 0xc00008f1d0 <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"), "IsBoolean", IsBoolean(Var("x")))
            )
        )
    ).get());
[{value: ["array"], IsBoolean: false},
 {value: true, IsBoolean: true},
 {value: false, IsBoolean: true},
 {value: [0x01 0x02 0x03 0x04], IsBoolean: false},
 {value: [1, 2, 3, 4], IsBoolean: false},
 {value: ref(id = "Letters", collection = ref(id = "collections")),
  IsBoolean: false},
 {value: ref(id = "248967019900174848", collection = ref(id = "credentials")),
  IsBoolean: false},
 {value: ref(id = "child_db", collection = ref(id = "databases")),
  IsBoolean: false},
 {value: 2019-11-12, IsBoolean: false},
 {value: ref(id = "123", collection = ref(id = "Letters", collection = ref(id = "collections"))),
  IsBoolean: false},
 {value: 10.1, IsBoolean: false},
 {value: ref(id = "double", collection = ref(id = "functions")),
  IsBoolean: false},
 {value: ref(id = "all_letters", collection = ref(id = "indexes")),
  IsBoolean: false},
 {value: 10, IsBoolean: false},
 {value: ref(id = "248967241620521472", collection = ref(id = "keys")),
  IsBoolean: false},
 {value: QueryV({lambda=x, expr={var=x}}), IsBoolean: false},
 {value: null, IsBoolean: false},
 {value: {x: 10}, IsBoolean: false},
 {value: ref(id = "employees", collection = ref(id = "roles")),
  IsBoolean: false},
 {value: {@set = {match: ref(id = "all_letters", collection = ref(id = "indexes"))}},
  IsBoolean: false},
 {value: "ten", IsBoolean: false},
 {value: "10", IsBoolean: false},
 {value: 2019-11-12T13:15:16.789Z, IsBoolean: false},
 {value: ref(id = "249062079147803136", collection = ref(id = "tokens")),
  IsBoolean: 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'),
      IsBoolean: q.IsBoolean(q.Var('x')),
    })
  )
)
.then((ret) => console.log(ret))
[ { value: [ 'array' ], IsBoolean: false },
  { value: true, IsBoolean: true },
  { value: false, IsBoolean: true },
  { value: Bytes("AQIDBA=="), IsBoolean: false },
  { value: [ 1, 2, 3, 4 ], IsBoolean: false },
  { value: Collection("Letters"), IsBoolean: false },
  { value: Ref(Credentials(), "248967019900174848"),
    IsBoolean: false },
  { value: Database("child_db"), IsBoolean: false },
  { value: Date("2019-11-12"), IsBoolean: false },
  { value: Ref(Collection("Letters"), "123"), IsBoolean: false },
  { value: 10.1, IsBoolean: false },
  { value: Function("double"), IsBoolean: false },
  { value: Index("all_letters"), IsBoolean: false },
  { value: 10, IsBoolean: false },
  { value: Ref(Keys(), "248967241620521472"), IsBoolean: false },
  { value: Query(Lambda("x", Var("x"))), IsBoolean: false },
  { value: null, IsBoolean: false },
  { value: { x: 10 }, IsBoolean: false },
  { value: Role("employees"), IsBoolean: false },
  { value: Match(Index("all_letters")), IsBoolean: false },
  { value: 'ten', IsBoolean: false },
  { value: '10', IsBoolean: false },
  { value: Time("2019-11-12T13:15:16.789Z"), IsBoolean: false },
  { value: Ref(Tokens(), "249062079147803136"), IsBoolean: 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"), "IsBoolean" -> IsBoolean(Var("x")))
      )
    )
  ),
  5.seconds
))
[{value: ["array"], IsBoolean: false},
 {value: true, IsBoolean: true},
 {value: false, IsBoolean: true},
 {value: [0x01 0x02 0x03 0x04], IsBoolean: false},
 {value: [1, 2, 3, 4], IsBoolean: false},
 {value: ref(id = "Letters", collection = ref(id = "collections")),
  IsBoolean: false},
 {value: ref(id = "248967019900174848", collection = ref(id = "credentials")),
  IsBoolean: false},
 {value: ref(id = "child_db", collection = ref(id = "databases")),
  IsBoolean: false},
 {value: 2019-11-12, IsBoolean: false},
 {value: ref(id = "123", collection = ref(id = "Letters", collection = ref(id = "collections"))),
  IsBoolean: false},
 {value: 10.1, IsBoolean: false},
 {value: ref(id = "double", collection = ref(id = "functions")),
  IsBoolean: false},
 {value: ref(id = "all_letters", collection = ref(id = "indexes")),
  IsBoolean: false},
 {value: 10, IsBoolean: false},
 {value: ref(id = "248967241620521472", collection = ref(id = "keys")),
  IsBoolean: false},
 {value: {lambda: "x", expr: {var: "x"}}, IsBoolean: false},
 {value: NullV, IsBoolean: false},
 {value: {x: 10}, IsBoolean: false},
 {value: ref(id = "employees", collection = ref(id = "roles")),
  IsBoolean: false},
 {value: {@set = {match: ref(id = "all_letters", collection = ref(id = "indexes"))}},
  IsBoolean: false},
 {value: "ten", IsBoolean: false},
 {value: "10", IsBoolean: false},
 {value: 2019-11-12T13:15:16.789Z, IsBoolean: false},
 {value: ref(id = "249062079147803136", collection = ref(id = "tokens")),
  IsBoolean: 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.

Was this article helpful?

We're sorry to hear that.
Tell us how we can improve!
Visit Fauna's Discourse forums or email docs@fauna.com

Thank you for your feedback!