typedArray.fill

The fill() method fills all the elements of a typed array from a start index to an end index with a static value. This method has the same algorithm as Array.prototype.fill(). TypedArray is one of the typed array types here.

Syntax

typedarray.fill(value[, start = 0[, end = this.length]])

Parameters

value

Value to fill the typed array with.

start

Optional. Start index. Defaults to 0.

end

Optional. End index (not included). Defaults to this.length.

Return value

The modified array.

Description

The elements interval to fill is [start, end).

The fill method takes up to three arguments value, start and end. The start and end arguments are optional with default values of 0 and the length of the this object.

If start is negative, it is treated as length+start where length is the length of the array. If end is negative, it is treated as length+end.

Examples

new Uint8Array([1, 2, 3]).fill(4);         // Uint8Array [4, 4, 4]
new Uint8Array([1, 2, 3]).fill(4, 1);      // Uint8Array [1, 4, 4]
new Uint8Array([1, 2, 3]).fill(4, 1, 2);   // Uint8Array [1, 4, 3]
new Uint8Array([1, 2, 3]).fill(4, 1, 1);   // Uint8Array [1, 2, 3]
new Uint8Array([1, 2, 3]).fill(4, -3, -2); // Uint8Array [4, 2, 3]

Polyfill

Since there is no global object with the name TypedArray, polyfilling must be done on an "as needed" basis. Use the following "polyfill" along with the Array.prototype.fill() polyfill.

// https://tc39.github.io/ecma262/#sec-%typedarray%.prototype.fill
if (!Uint8Array.prototype.fill) {
  Uint8Array.prototype.fill = Array.prototype.fill;
}

Specifications

Specification	Status	Comment
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'TypedArray.prototype.fill' in that specification.	Standard	Initial definition.
ECMAScript 2017 Draft (ECMA-262) The definition of 'TypedArray.prototype.fill' in that specification.	Draft

Browser compatibility

See also

• Array.prototype.fill()