diff --git a/lib/node_modules/@stdlib/array/uint64/README.md b/lib/node_modules/@stdlib/array/uint64/README.md
index 02da19409141..eb6a2ed4f384 100644
--- a/lib/node_modules/@stdlib/array/uint64/README.md
+++ b/lib/node_modules/@stdlib/array/uint64/README.md
@@ -278,6 +278,103 @@ u = arr.at( -100 );
// returns undefined
```
+
+
+#### Uint64Array.prototype.copyWithin( target, start\[, end] )
+
+Copies a sequence of elements within the array starting at `start` and ending at `end` (non-inclusive) to the position starting at `target`.
+
+```javascript
+var Uint64 = require( '@stdlib/number/uint64/ctor' );
+
+var arr = new Uint64Array( 4 );
+
+// Set the array elements:
+arr.set( 1, 0 );
+arr.set( 2, 1 );
+arr.set( 3, 2 );
+arr.set( 4, 3 );
+
+// Get the first array element:
+var z = arr.get( 0 );
+// returns [ 1n ]
+
+// Get the second array element:
+z = arr.get( 1 );
+// returns [ 2n ]
+
+// Copy the last two elements to the first two elements:
+arr.copyWithin( 0, 2 );
+
+// Get the first array element:
+z = arr.get( 0 );
+// returns [ 3n ]
+
+// Get the second array element:
+z = arr.get( 1 );
+// returns [ 4n ]
+```
+
+By default, `end` equals the number of array elements (i.e., one more than the last array index). To limit the sequence length, provide an `end` argument.
+
+```javascript
+var Uint64 = require( '@stdlib/number/uint64/ctor' );
+
+var arr = new Uint64Array( 4 );
+
+// Set the array elements:
+arr.set( 1, 0 );
+arr.set( 2, 1 );
+arr.set( 3, 2 );
+arr.set( 4, 3 );
+
+// Get the third array element:
+var z = arr.get( 2 );
+// returns [ 3n ]
+
+// Get the last array element:
+z = arr.get( 3 );
+// returns [ 4n ]
+
+// Copy the first two elements to the last two elements:
+arr.copyWithin( 2, 0, 2 );
+
+// Get the third array element:
+z = arr.get( 2 );
+// returns [ 1n ]
+
+// Get the last array element:
+z = arr.get( 3 );
+// returns [ 2n ]
+```
+
+When a `target`, `start`, and/or `end` index is negative, the respective index is determined relative to the last array element. The following example achieves the same behavior as the previous example:
+
+```javascript
+var Uint64 = require( '@stdlib/number/uint64/ctor' );
+
+var arr = new Uint64Array( [ 1, 2, 3, 4 ] );
+
+// Get the third array element:
+var z = arr.get( 2 );
+// returns [ 3n ]
+
+// Get the last array element:
+z = arr.get( 3 );
+// returns [ 4n ]
+
+// Copy the first two elements to the last two elements using negative indices:
+arr.copyWithin( -2, -4, -2 );
+
+// Get the third array element:
+z = arr.get( 2 );
+// returns [ 1n ]
+
+// Get the last array element:
+z = arr.get( 3 );
+// returns [ 2n ]
+```
+
#### Uint64Array.prototype.entries()
diff --git a/lib/node_modules/@stdlib/array/uint64/benchmark/benchmark.copy_within.js b/lib/node_modules/@stdlib/array/uint64/benchmark/benchmark.copy_within.js
new file mode 100644
index 000000000000..d416f14ae33a
--- /dev/null
+++ b/lib/node_modules/@stdlib/array/uint64/benchmark/benchmark.copy_within.js
@@ -0,0 +1,53 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var bench = require( '@stdlib/bench' );
+var isUint64Array = require( '@stdlib/assert/is-uint64array' );
+var format = require( '@stdlib/string/format' );
+var pkg = require( './../package.json' ).name;
+var Uint64Array = require( './../lib' );
+
+
+// MAIN //
+
+bench( format( '%s:copyWithin', pkg ), function benchmark( b ) {
+ var arr;
+ var out;
+ var i;
+
+ arr = new Uint64Array( 10 );
+
+ // Benchmark worst case scenario (i.e., copying all but one element to an overlapping region)...
+ b.tic();
+ for ( i = 0; i < b.iterations; i++ ) {
+ out = arr.copyWithin( 1, 0 );
+ if ( typeof out !== 'object' ) {
+ b.fail( 'should return an object' );
+ }
+ }
+ b.toc();
+ if ( !isUint64Array( out ) ) {
+ b.fail( 'should return a Uint64Array' );
+ }
+ b.pass( 'benchmark finished' );
+ b.end();
+});
diff --git a/lib/node_modules/@stdlib/array/uint64/benchmark/benchmark.copy_within.length.js b/lib/node_modules/@stdlib/array/uint64/benchmark/benchmark.copy_within.length.js
new file mode 100644
index 000000000000..80678f6ca5d2
--- /dev/null
+++ b/lib/node_modules/@stdlib/array/uint64/benchmark/benchmark.copy_within.length.js
@@ -0,0 +1,96 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var bench = require( '@stdlib/bench' );
+var pow = require( '@stdlib/math/base/special/pow' );
+var isUint64Array = require( '@stdlib/assert/is-uint64array' );
+var format = require( '@stdlib/string/format' );
+var pkg = require( './../package.json' ).name;
+var Uint64Array = require( './../lib' );
+
+
+// FUNCTIONS //
+
+/**
+* Creates a benchmark function.
+*
+* @private
+* @param {PositiveInteger} len - array length
+* @returns {Function} benchmark function
+*/
+function createBenchmark( len ) {
+ var arr = new Uint64Array( len );
+ return benchmark;
+
+ /**
+ * Benchmark function.
+ *
+ * @private
+ * @param {Benchmark} b - benchmark instance
+ */
+ function benchmark( b ) {
+ var out;
+ var i;
+
+ // Benchmark worst case scenario (i.e., copying all but one element to an overlapping region)...
+ b.tic();
+ for ( i = 0; i < b.iterations; i++ ) {
+ out = arr.copyWithin( 1, 0 );
+ if ( typeof out !== 'object' ) {
+ b.fail( 'should return an object' );
+ }
+ }
+ b.toc();
+ if ( !isUint64Array( out ) ) {
+ b.fail( 'should return a Uint64Array' );
+ }
+ b.pass( 'benchmark finished' );
+ b.end();
+ }
+}
+
+
+// MAIN //
+
+/**
+* Main execution sequence.
+*
+* @private
+*/
+function main() {
+ var len;
+ var min;
+ var max;
+ var f;
+ var i;
+
+ min = 1; // 10^min
+ max = 6; // 10^max
+
+ for ( i = min; i <= max; i++ ) {
+ len = pow( 10, i );
+ f = createBenchmark( len );
+ bench( format( '%s:copyWithin:len=%d', pkg, len ), f );
+ }
+}
+
+main();
diff --git a/lib/node_modules/@stdlib/array/uint64/benchmark/benchmark.get.js b/lib/node_modules/@stdlib/array/uint64/benchmark/benchmark.get.js
index bee09657497b..def833746eb2 100644
--- a/lib/node_modules/@stdlib/array/uint64/benchmark/benchmark.get.js
+++ b/lib/node_modules/@stdlib/array/uint64/benchmark/benchmark.get.js
@@ -36,8 +36,7 @@ bench( format( '%s:get', pkg ), function benchmark( b ) {
var v;
var i;
- arr = zeroTo( 10, 'generic' );
- arr = new Uint64Array( arr );
+ arr = new Uint64Array( zeroTo( 10, 'generic' ) );
N = arr.length;
b.tic();
diff --git a/lib/node_modules/@stdlib/array/uint64/docs/repl.txt b/lib/node_modules/@stdlib/array/uint64/docs/repl.txt
index c737fc5bf588..8098f50dba68 100644
--- a/lib/node_modules/@stdlib/array/uint64/docs/repl.txt
+++ b/lib/node_modules/@stdlib/array/uint64/docs/repl.txt
@@ -252,6 +252,35 @@
[ 2n ]
+{{alias}}.prototype.copyWithin( target, start[, end] )
+ Copies a sequence of elements within the array starting at `start` and
+ ending at `end` (non-inclusive) to the position starting at `target`.
+
+ Parameters
+ ----------
+ target: integer
+ Target start index position.
+
+ start: integer
+ Source start index position.
+
+ end: integer (optional)
+ Source end index position. Default: out.length.
+
+ Returns
+ -------
+ out: Uint64Array
+ Modified array.
+
+ Examples
+ --------
+ > var arr = new {{alias}}( [ 1, 2, 3, 4 ] );
+ > arr.copyWithin( 0, 2 )
+ [ 3n, 4n, 3n, 4n ]
+ > var z = arr.get( 0 )
+ [ 3n ]
+
+
{{alias}}.prototype.entries()
Returns an iterator for iterating over array key-value pairs.
diff --git a/lib/node_modules/@stdlib/array/uint64/docs/types/index.d.ts b/lib/node_modules/@stdlib/array/uint64/docs/types/index.d.ts
index 78b11c503625..0643dba70b4a 100644
--- a/lib/node_modules/@stdlib/array/uint64/docs/types/index.d.ts
+++ b/lib/node_modules/@stdlib/array/uint64/docs/types/index.d.ts
@@ -426,6 +426,25 @@ declare class Uint64Array implements Uint64ArrayInterface {
*/
at( i: number ): Uint64 | void;
+ /**
+ * Copies a sequence of elements within the array to the position starting at `target`.
+ *
+ * @param target - index at which to start copying elements
+ * @param start - source index at which to copy elements from
+ * @param end - source index at which to stop copying elements from
+ * @returns modified array
+ *
+ * @example
+ * var Uint64 = require( '@stdlib/number/uint64/ctor' );
+ *
+ * var arr = new Uint64Array( [ 1, 2, 3, 4 ] );
+ *
+ * // Copy the first two elements to the last two elements:
+ * arr.copyWithin( 2, 0, 2 );
+ * // arr => [ 1n, 2n, 1n, 2n ]
+ */
+ copyWithin( target: number, start: number, end?: number ): Uint64Array;
+
/**
* Returns an iterator for iterating over array key-value pairs.
*
diff --git a/lib/node_modules/@stdlib/array/uint64/lib/main.js b/lib/node_modules/@stdlib/array/uint64/lib/main.js
index 684cb8e4b9bd..5b0b4eb7125a 100644
--- a/lib/node_modules/@stdlib/array/uint64/lib/main.js
+++ b/lib/node_modules/@stdlib/array/uint64/lib/main.js
@@ -597,6 +597,40 @@ setReadOnlyAccessor( Uint64Array.prototype, 'byteOffset', function get() {
*/
setReadOnly( Uint64Array.prototype, 'BYTES_PER_ELEMENT', Uint64Array.BYTES_PER_ELEMENT );
+/**
+* Copies a sequence of elements within the array to the position starting at `target`.
+*
+* @name copyWithin
+* @memberof Uint64Array.prototype
+* @type {Function}
+* @param {integer} target - index at which to start copying elements
+* @param {integer} start - source index at which to copy elements from
+* @param {integer} [end] - source index at which to stop copying elements from
+* @throws {TypeError} `this` must be a 64-bit unsigned integer array
+* @returns {Uint64Array} modified array
+*
+* @example
+* var Uint64 = require( '@stdlib/number/uint64/ctor' );
+*
+* var arr = new Uint64Array( [ 1, 2, 3, 4 ] );
+*
+* // Copy the first two elements to the last two elements:
+* arr.copyWithin( 2, 0, 2 );
+* // arr => [ 1n, 2n, 1n, 2n ]
+*/
+setReadOnly( Uint64Array.prototype, 'copyWithin', function copyWithin( target, start ) {
+ if ( !isUint64Array( this ) ) {
+ throw new TypeError( 'invalid invocation. `this` is not a 64-bit unsigned integer array.' );
+ }
+ // FIXME: prefer a functional `copyWithin` implementation which addresses lack of universal browser support (e.g., IE11 and Safari) or ensure that typed arrays are polyfilled
+ if ( arguments.length === 2 ) {
+ this._buffer.copyWithin( target*2, start*2 );
+ } else {
+ this._buffer.copyWithin( target*2, start*2, arguments[2]*2 );
+ }
+ return this;
+});
+
/**
* Returns an iterator for iterating over array key-value pairs.
*
diff --git a/lib/node_modules/@stdlib/array/uint64/test/test.copy_within.js b/lib/node_modules/@stdlib/array/uint64/test/test.copy_within.js
new file mode 100644
index 000000000000..d1d4ce4b4918
--- /dev/null
+++ b/lib/node_modules/@stdlib/array/uint64/test/test.copy_within.js
@@ -0,0 +1,257 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var tape = require( 'tape' );
+var hasOwnProp = require( '@stdlib/assert/has-own-property' );
+var isEqual = require( '@stdlib/number/uint64/base/assert/is-equal' );
+var isFunction = require( '@stdlib/assert/is-function' );
+var Uint64 = require( '@stdlib/number/uint64/ctor' );
+var Uint64Array = require( './../lib' );
+
+
+// TESTS //
+
+tape( 'main export is a function', function test( t ) {
+ t.ok( true, __filename );
+ t.strictEqual( typeof Uint64Array, 'function', 'main export is a function' );
+ t.end();
+});
+
+tape( 'attached to the prototype of the main export is a `copyWithin` method for copying a sequence of array elements within a 64-bit unsigned integer array', function test( t ) {
+ t.strictEqual( hasOwnProp( Uint64Array.prototype, 'copyWithin' ), true, 'has property' );
+ t.strictEqual( isFunction( Uint64Array.prototype.copyWithin ), true, 'has method' );
+ t.end();
+});
+
+tape( 'the method throws an error if invoked with a `this` context which is not a 64-bit unsigned integer array instance', function test( t ) {
+ var values;
+ var arr;
+ var i;
+
+ arr = new Uint64Array( 5 );
+
+ values = [
+ '5',
+ 5,
+ NaN,
+ true,
+ false,
+ null,
+ void 0,
+ {},
+ []
+ ];
+ for ( i = 0; i < values.length; i++ ) {
+ t.throws( badValue( values[i] ), TypeError, 'throws an error when provided '+values[i] );
+ }
+ t.end();
+
+ function badValue( value ) {
+ return function badValue() {
+ return arr.copyWithin.call( value, 3, 0 );
+ };
+ }
+});
+
+tape( 'the method throws an error if invoked with a `this` context which is not a 64-bit unsigned integer array instance (end)', function test( t ) {
+ var values;
+ var arr;
+ var i;
+
+ arr = new Uint64Array( 5 );
+
+ values = [
+ '5',
+ 5,
+ NaN,
+ true,
+ false,
+ null,
+ void 0,
+ {},
+ []
+ ];
+ for ( i = 0; i < values.length; i++ ) {
+ t.throws( badValue( values[i] ), TypeError, 'throws an error when provided '+values[i] );
+ }
+ t.end();
+
+ function badValue( value ) {
+ return function badValue() {
+ return arr.copyWithin.call( value, 3, 0, 5 );
+ };
+ }
+});
+
+tape( 'the method copies a sequence of elements within an array', function test( t ) {
+ var arr;
+
+ arr = new Uint64Array( [ 0, 1, 2, 3, 4 ] );
+
+ arr.copyWithin( 0, 3 );
+
+ // Overwritten:
+ t.strictEqual( isEqual( arr.get( 0 ), new Uint64( 3 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 1 ), new Uint64( 4 ) ), true, 'returns expected value' );
+
+ // Remain the same:
+ t.strictEqual( isEqual( arr.get( 2 ), new Uint64( 2 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 3 ), new Uint64( 3 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 4 ), new Uint64( 4 ) ), true, 'returns expected value' );
+
+ t.end();
+});
+
+tape( 'the method copies a sequence of elements within an array (negative target)', function test( t ) {
+ var arr;
+
+ arr = new Uint64Array( [ 0, 1, 2, 3, 4 ] );
+
+ arr.copyWithin( -arr.length, 3 );
+
+ // Overwritten:
+ t.strictEqual( isEqual( arr.get( 0 ), new Uint64( 3 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 1 ), new Uint64( 4 ) ), true, 'returns expected value' );
+
+ // Remain the same:
+ t.strictEqual( isEqual( arr.get( 2 ), new Uint64( 2 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 3 ), new Uint64( 3 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 4 ), new Uint64( 4 ) ), true, 'returns expected value' );
+
+ t.end();
+});
+
+tape( 'the method copies a sequence of elements within an array (negative start)', function test( t ) {
+ var arr;
+
+ arr = new Uint64Array( [ 0, 1, 2, 3, 4 ] );
+
+ arr.copyWithin( 0, -2 );
+
+ // Overwritten:
+ t.strictEqual( isEqual( arr.get( 0 ), new Uint64( 3 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 1 ), new Uint64( 4 ) ), true, 'returns expected value' );
+
+ // Remain the same:
+ t.strictEqual( isEqual( arr.get( 2 ), new Uint64( 2 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 3 ), new Uint64( 3 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 4 ), new Uint64( 4 ) ), true, 'returns expected value' );
+
+ t.end();
+});
+
+tape( 'the method copies a sequence of elements within an array (end=length)', function test( t ) {
+ var arr;
+
+ arr = new Uint64Array( [ 0, 1, 2, 3, 4 ] );
+
+ arr.copyWithin( 0, 3, arr.length );
+
+ // Overwritten:
+ t.strictEqual( isEqual( arr.get( 0 ), new Uint64( 3 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 1 ), new Uint64( 4 ) ), true, 'returns expected value' );
+
+ // Remain the same:
+ t.strictEqual( isEqual( arr.get( 2 ), new Uint64( 2 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 3 ), new Uint64( 3 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 4 ), new Uint64( 4 ) ), true, 'returns expected value' );
+
+ t.end();
+});
+
+tape( 'the method copies a sequence of elements within an array (non-inclusive end)', function test( t ) {
+ var arr;
+
+ arr = new Uint64Array( [ 0, 1, 2, 3, 4 ] );
+
+ arr.copyWithin( 2, 0, 2 );
+
+ // Remain the same:
+ t.strictEqual( isEqual( arr.get( 0 ), new Uint64( 0 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 1 ), new Uint64( 1 ) ), true, 'returns expected value' );
+
+ // Overwritten:
+ t.strictEqual( isEqual( arr.get( 2 ), new Uint64( 0 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 3 ), new Uint64( 1 ) ), true, 'returns expected value' );
+
+ // Remain the same:
+ t.strictEqual( isEqual( arr.get( 4 ), new Uint64( 4 ) ), true, 'returns expected value' );
+
+ t.end();
+});
+
+tape( 'the method copies a sequence of elements within an array (negative end)', function test( t ) {
+ var arr;
+
+ arr = new Uint64Array( [ 0, 1, 2, 3, 4 ] );
+
+ arr.copyWithin( 2, 0, -3 );
+
+ // Remain the same:
+ t.strictEqual( isEqual( arr.get( 0 ), new Uint64( 0 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 1 ), new Uint64( 1 ) ), true, 'returns expected value' );
+
+ // Overwritten:
+ t.strictEqual( isEqual( arr.get( 2 ), new Uint64( 0 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 3 ), new Uint64( 1 ) ), true, 'returns expected value' );
+
+ // Remain the same:
+ t.strictEqual( isEqual( arr.get( 4 ), new Uint64( 4 ) ), true, 'returns expected value' );
+
+ t.end();
+});
+
+tape( 'the method copies a sequence of elements within an array (target >= length)', function test( t ) {
+ var arr;
+
+ arr = new Uint64Array( [ 0, 1, 2, 3, 4 ] );
+
+ arr.copyWithin( arr.length, 3 );
+
+ // Remain the same:
+ t.strictEqual( isEqual( arr.get( 0 ), new Uint64( 0 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 1 ), new Uint64( 1 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 2 ), new Uint64( 2 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 3 ), new Uint64( 3 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 4 ), new Uint64( 4 ) ), true, 'returns expected value' );
+
+ t.end();
+});
+
+tape( 'the method copies a sequence of elements within an array (target > start)', function test( t ) {
+ var arr;
+
+ arr = new Uint64Array( [ 0, 1, 2, 3, 4 ] );
+
+ arr.copyWithin( 2, 0 );
+
+ // Remain the same:
+ t.strictEqual( isEqual( arr.get( 0 ), new Uint64( 0 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 1 ), new Uint64( 1 ) ), true, 'returns expected value' );
+
+ // Overwritten:
+ t.strictEqual( isEqual( arr.get( 2 ), new Uint64( 0 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 3 ), new Uint64( 1 ) ), true, 'returns expected value' );
+ t.strictEqual( isEqual( arr.get( 4 ), new Uint64( 2 ) ), true, 'returns expected value' );
+
+ t.end();
+});