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Prepend

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

 
Prepend( elems, base )
prepend( elems, base )
Prepend( elems, base )
Prepend( elems, base )
Prepend( elems, base )

Description

The Prepend function creates a new Array that is the result of combining the elems followed by the base Array. This function only works with Arrays, not with Pages.

Parameters

Parameter Type Definition and Requirements

base

Array

The base Array.

elems

Value or Array

The elements to add to the beginning of the base Array.

Returns

A new Array containing the elems followed by the base Array.

Examples

A new array containing the elems array values, (1, 2, 3), followed by the array values, (4, 5, 6):

client.query(
  q.Prepend([1, 2, 3], [4, 5, 6])
)
.then((ret) => console.log(ret))
.catch((err) => console.error(
  'Error: [%s] %s: %s',
  err.name,
  err.message,
  err.errors()[0].description,
))
[ 1, 2, 3, 4, 5, 6 ]
result = client.query(
  q.prepend([1, 2, 3], [4, 5, 6])
)
print(result)
[1, 2, 3, 4, 5, 6]
result, err := client.Query(
	f.Prepend(f.Arr{1, 2, 3}, f.Arr{4, 5, 6}))

if err != nil {
	fmt.Fprintln(os.Stderr, err)
} else {
	fmt.Println(result)
}
[1 2 3 4 5 6]
try
{
    Value result = await client.Query(
        Prepend(Arr(1, 2, 3), Arr(4, 5, 6))
    );
    Console.WriteLine(result);
}
catch (Exception e)
{
    Console.WriteLine($"ERROR: {e.Message}");
}
Arr(LongV(1), LongV(2), LongV(3), LongV(4), LongV(5), LongV(6))
Prepend([1, 2, 3], [4, 5, 6])
[ 1, 2, 3, 4, 5, 6 ]
Query metrics:

  •    bytesIn:  40

  •   bytesOut:  26

  • computeOps:   1

  •    readOps:   0

  •   writeOps:   0

  •  readBytes:   0

  • writeBytes:   0

  •  queryTime: 2ms

  •    retries:   0

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