API UInt64Array

UInt64Array

Fixed-length packed array of unsigned 64-bit integers.

Script API Reference

Overview

UInt64Array is a primitive-backed array for wide non-negative integer data such as 64-bit hashes, bit masks, and large sequence numbers. Elements live in contiguous native storage, so the array avoids the per-element object allocation of a general Array.

The length is fixed at construction. push, pop, and element deletion are unavailable; elements are read and written through numeric indexes.

var masks = new UInt64Array(2);
masks[0] = 1048576;
return masks[0]; // 1048576

Warning

Indexing outside 0 to length - 1 raises a runtime error. Validate computed indexes before reading or writing.

Note

Script number values are double-precision. Integers above Number.MAX_SAFE_INTEGER cannot be represented exactly as a script number, so they may lose precision on the way into or out of the array.

Constructors

new UInt64Array([length])

Parameters

Name	Type	Required	Description
length	number	No	Non-negative element count. Omitting it creates an empty array.

Returns

UInt64Array — a fixed-length array whose elements start at 0.

Example

var sequences = new UInt64Array(4);
return sequences[3]; // 0

Properties

values.length

Returns

number — the fixed element count.

Behavior

Read-only. The value never changes for a given instance.

Example

return new UInt64Array(8).length; // 8

Methods

values.fill([value])

Parameters

Name	Type	Required	Description
value	number	No	Value written to every element. Defaults to 0.

Returns

UInt64Array — this array, so calls can be chained.

Behavior

The value is converted to an unsigned 64-bit integer before it is stored, and every element is overwritten in place.

Example

var masks = new UInt64Array(3);
masks.fill(1024);
return masks[2]; // 1024