IsIndex

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( value )

Description

The IsIndex function returns true only if value is an index, 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 index or not.

Returns

Returns a boolean, indicating whether value was an index 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 IsIndex with that value:

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(
  [
    ['array'],
    true,
    false,
    new Uint8Array([1, 2, 3, 4]),
    [0x1, 0x2, 0x3, 0x4],
    ('Letters'),
    ('credentials/self'),
    ('child_db'),
    ('2019-11-12'),
    (('Letters'), 123),
    10.1,
    ('double'),
    ('letters'),
    10,
    ((), '1'),
    (('x', ('x'))),
    null,
    { x: 10 },
    ('employees'),
    (('letters')),
    'ten',
    '10',
    ('2020-07-06T12:34:56.789Z'),
    ((), '1'),
  ],
  ('x', {
    value: ('x'),
    IsIndex: (('x')),
  })
)
[
  { value: [ 'array' ], IsIndex: false },
  { value: true, IsIndex: false },
  { value: false, IsIndex: false },
  { value: { '0': 1, '1': 2, '2': 3, '3': 4 }, IsIndex: false },
  { value: [ 1, 2, 3, 4 ], IsIndex: false },
  { value: ("Letters"), IsIndex: false },
  { value: ((), "302043979982045696"), IsIndex: false },
  { value: ("child_db"), IsIndex: false },
  { value: ("2019-11-12"), IsIndex: false },
  { value: (("Letters"), "123"), IsIndex: false },
  { value: 10.1, IsIndex: false },
  { value: ("double"), IsIndex: false },
  { value: ("letters"), IsIndex: true },
  { value: 10, IsIndex: false },
  { value: ((), "1"), IsIndex: false },
  { value: (("x", ("x"))), IsIndex: false },
  { value: null, IsIndex: false },
  { value: { x: 10 }, IsIndex: false },
  { value: ("employees"), IsIndex: false },
  { value: (("letters")), IsIndex: false },
  { value: 'ten', IsIndex: false },
  { value: '10', IsIndex: false },
  { value: ("2020-07-06T12:34:56.789Z"), IsIndex: false },
  { value: ((), "1"), IsIndex: false }
]
Query metrics:

  •    bytesIn:   598

  •   bytesOut: 1,559

  • computeOps:     2

  •    readOps:     0

  •   writeOps:     0

  •  readBytes:   373

  • writeBytes:     0

  •  queryTime:  21ms

  •    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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