IsCollection
IsCollection( value )
Description
The IsCollection
function returns true
only if value
is a
collection, otherwise it returns
false
.
Parameters
Parameter | Type | Definition and Requirements |
---|---|---|
|
Any value, which is to be tested to determine whether it is a collection or not. |
Returns
Returns a Boolean, indicating whether value
was 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:
[
{ value: [ 'array' ], IsCollection: false },
{ value: true, IsCollection: false },
{ value: false, IsCollection: false },
{ value: { '0': 1, '1': 2, '2': 3, '3': 4 }, IsCollection: false },
{ value: [ 1, 2, 3, 4 ], IsCollection: false },
{ value: Collection("Letters"), IsCollection: true },
{
value: Ref(Credentials(), "302043979982045696"),
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("letters"), IsCollection: false },
{ value: 10, IsCollection: false },
{ value: Ref(Keys(), "1"), 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("letters")), IsCollection: false },
{ value: 'ten', IsCollection: false },
{ value: '10', IsCollection: false },
{ value: Time("2020-07-06T12:34:56.789Z"), IsCollection: false },
{ value: Ref(Tokens(), "1"), 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 the |
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