IsCollection
Not available in this language yet.IsCollection( value )IsCollection( value )IsCollection( value )Not available in this language yet.IsCollection( value )Description
The IsCollection function returns true only if value is a
collection, otherwise it returns false.
Parameters
| Argument | Type | Definition and Requirements |
|---|---|---|
|
Any |
Any value, which is to be tested to determine whether it is a collection 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 IsCollection
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"),
"IsCollection": f.IsCollection(f.Var("x")),
})))
if (err != nil) {
fmt.Println(err)
} else {
fmt.Println(result)
}[map[IsCollection:false value:[array]] map[IsCollection:false value:true] map[IsCollection:false value:false] map[IsCollection:false value:[1 2 3 4]] map[IsCollection:false value:[1 2 3 4]] map[IsCollection:true value:{Letters 0xc00016a240 0xc00016a240 <nil>}] map[IsCollection:false value:{264354436692836874 0xc00016a390 0xc00016a390 <nil>}] map[IsCollection:false value:{child_db 0xc00016a4b0 0xc00016a4b0 <nil>}] map[IsCollection:false value:{0 63709113600 <nil>}] map[IsCollection:false value:{123 0xc00016a7e0 0xc00016a7e0 <nil>}] map[IsCollection:false value:10.1] map[IsCollection:false value:{double 0xc00016a930 0xc00016a930 <nil>}] map[IsCollection:false value:{all_letters 0xc00016aa50 0xc00016aa50 <nil>}] map[IsCollection:false value:10] map[IsCollection:false value:{248967241620521472 0xc00016aba0 0xc00016aba0 <nil>}] map[IsCollection: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[IsCollection:false value:{}] map[IsCollection:false value:{}] map[IsCollection:false value:map[x:10]] map[IsCollection:false value:{employees 0xc00016adb0 0xc00016adb0 <nil>}] map[IsCollection:false value:{map[match:{all_letters 0xc00016af00 0xc00016af00 <nil>}]}] map[IsCollection:false value:ten] map[IsCollection:false value:10] map[IsCollection:false value:{808091000 63724302168 <nil>}] map[IsCollection:false value:{249062079147803136 0xc00016b0b0 0xc00016b0b0 <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"), "IsCollection", IsCollection(Var("x")))
)
)
).get());[{value: ["array"], IsCollection: false},
{value: true, IsCollection: false},
{value: false, IsCollection: false},
{value: [0x01 0x02 0x03 0x04], IsCollection: false},
{value: [1, 2, 3, 4], IsCollection: false},
{value: ref(id = "Letters", collection = ref(id = "collections")),
IsCollection: true},
{value: ref(id = "248967019900174848", collection = ref(id = "credentials")),
IsCollection: false},
{value: ref(id = "child_db", collection = ref(id = "databases")),
IsCollection: false},
{value: 2019-11-12, IsCollection: false},
{value: ref(id = "123", collection = ref(id = "Letters", collection = ref(id = "collections"))),
IsCollection: false},
{value: 10.1, IsCollection: false},
{value: ref(id = "double", collection = ref(id = "functions")),
IsCollection: false},
{value: ref(id = "all_letters", collection = ref(id = "indexes")),
IsCollection: false},
{value: 10, IsCollection: false},
{value: ref(id = "248967241620521472", collection = ref(id = "keys")),
IsCollection: false},
{value: QueryV({lambda=x, expr={var=x}}), IsCollection: false},
{value: null, IsCollection: false},
{value: {x: 10}, IsCollection: false},
{value: ref(id = "employees", collection = ref(id = "roles")),
IsCollection: false},
{value: {@set = {match: ref(id = "all_letters", collection = ref(id = "indexes"))}},
IsCollection: false},
{value: "ten", IsCollection: false},
{value: "10", IsCollection: false},
{value: 2019-11-12T13:15:16.789Z, IsCollection: false},
{value: ref(id = "249062079147803136", collection = ref(id = "tokens")),
IsCollection: 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'),
IsCollection: q.IsCollection(q.Var('x')),
})
)
)
.then((ret) => console.log(ret))[ { value: [ 'array' ], IsCollection: false },
{ value: true, IsCollection: false },
{ value: false, IsCollection: false },
{ value: Bytes("AQIDBA=="), IsCollection: false },
{ value: [ 1, 2, 3, 4 ], IsCollection: false },
{ value: Collection("Letters"), IsCollection: true },
{ value: Ref(Credentials(), "248967019900174848"),
IsCollection: false },
{ value: Database("child_db"), IsCollection: false },
{ value: Date("2019-11-12"), IsCollection: false },
{ value: Ref(Collection("Letters"), "123"),
IsCollection: false },
{ value: 10.1, IsCollection: false },
{ value: Function("double"), IsCollection: false },
{ value: Index("all_letters"), IsCollection: false },
{ value: 10, IsCollection: false },
{ value: Ref(Keys(), "248967241620521472"),
IsCollection: false },
{ value: Query(Lambda("x", Var("x"))), IsCollection: false },
{ value: null, IsCollection: false },
{ value: { x: 10 }, IsCollection: false },
{ value: Role("employees"), IsCollection: false },
{ value: Match(Index("all_letters")), IsCollection: false },
{ value: 'ten', IsCollection: false },
{ value: '10', IsCollection: false },
{ value: Time("2019-11-12T13:15:16.789Z"), IsCollection: false },
{ value: Ref(Tokens(), "249062079147803136"),
IsCollection: 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"), "IsCollection" -> IsCollection(Var("x")))
)
)
),
5.seconds
))[{value: ["array"], IsCollection: false},
{value: true, IsCollection: false},
{value: false, IsCollection: false},
{value: [0x01 0x02 0x03 0x04], IsCollection: false},
{value: [1, 2, 3, 4], IsCollection: false},
{value: ref(id = "Letters", collection = ref(id = "collections")),
IsCollection: true},
{value: ref(id = "248967019900174848", collection = ref(id = "credentials")),
IsCollection: false},
{value: ref(id = "child_db", collection = ref(id = "databases")),
IsCollection: false},
{value: 2019-11-12, IsCollection: false},
{value: ref(id = "123", collection = ref(id = "Letters", collection = ref(id = "collections"))),
IsCollection: false},
{value: 10.1, IsCollection: false},
{value: ref(id = "double", collection = ref(id = "functions")),
IsCollection: false},
{value: ref(id = "all_letters", collection = ref(id = "indexes")),
IsCollection: false},
{value: 10, IsCollection: false},
{value: ref(id = "248967241620521472", collection = ref(id = "keys")),
IsCollection: false},
{value: {lambda: "x", expr: {var: "x"}}, IsCollection: false},
{value: NullV, IsCollection: false},
{value: {x: 10}, IsCollection: false},
{value: ref(id = "employees", collection = ref(id = "roles")),
IsCollection: false},
{value: {@set = {match: ref(id = "all_letters", collection = ref(id = "indexes"))}},
IsCollection: false},
{value: "ten", IsCollection: false},
{value: "10", IsCollection: false},
{value: 2019-11-12T13:15:16.789Z, IsCollection: false},
{value: ref(id = "249062079147803136", collection = ref(id = "tokens")),
IsCollection: 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
|
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