feat: add copyWithIn method to array/uint64

lib/node_modules/@stdlib/array/uint64/README.md

@@ -278,6 +278,103 @@ u = arr.at( -100 );
 // returns undefined
 ```
 
+<a name="method-copy-within"></a>
+
+#### 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 <Uint64>[ 1n ]
+
+// Get the second array element:
+z = arr.get( 1 );
+// returns <Uint64>[ 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 <Uint64>[ 3n ]
+
+// Get the second array element:
+z = arr.get( 1 );
+// returns <Uint64>[ 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 <Uint64>[ 3n ]
+
+// Get the last array element:
+z = arr.get( 3 );
+// returns <Uint64>[ 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 <Uint64>[ 1n ]
+
+// Get the last array element:
+z = arr.get( 3 );
+// returns <Uint64>[ 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 <Uint64>[ 3n ]
+
+// Get the last array element:
+z = arr.get( 3 );
+// returns <Uint64>[ 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 <Uint64>[ 1n ]
+
+// Get the last array element:
+z = arr.get( 3 );
+// returns <Uint64>[ 2n ]
+```
+
 <a name="method-entries"></a>
 
 #### Uint64Array.prototype.entries()

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();
+});

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();

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();

lib/node_modules/@stdlib/array/uint64/docs/repl.txt

@@ -252,6 +252,35 @@
     <Uint64>[ 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 )
+    <Uint64Array>[ 3n, 4n, 3n, 4n ]
+    > var z = arr.get( 0 )
+    <Uint64>[ 3n ]
+
+
 {{alias}}.prototype.entries()
     Returns an iterator for iterating over array key-value pairs.
 

lib/node_modules/@stdlib/array/uint64/docs/types/index.d.ts

@@ -28,7 +28,7 @@
 import ArrayBuffer = require( '@stdlib/array/buffer' );
 
 // Define a union type representing both iterable and non-iterable iterators:
 type Iterator = Iter | IterableIterator;
 
 // Define a type representing a value from which a 64-bit unsigned integer can be derived:
 type Uint = Uint64 | bigint | number;
@@ -36,7 +36,7 @@
 /**
 * Locale-specific configuration options.
 */
 interface LocaleOptions<T = unknown> {
 	/**
 	* Configuration property.
 	*/
@@ -118,7 +118,7 @@
 * @param arr - array on which the method was called
 * @returns boolean indicating whether an element in an array passes a test
 */
 type Predicate<U> = NullaryPredicate<U> | UnaryPredicate<U> | BinaryPredicate<U> | TernaryPredicate<U>;
 
 /**
 * Callback invoked for each element in an array.
@@ -162,7 +162,7 @@
 * @param arr - array on which the method was called
 * @returns undefined
 */
 type Callback<U> = NullaryCallback<U> | UnaryCallback<U> | BinaryCallback<U> | TernaryCallback<U>;
 
 /**
 * Callback invoked for each element in an array.
@@ -206,7 +206,7 @@
 * @param arr - array on which the method was called
 * @returns transformed value
 */
 type MapFcn<U> = NullaryMapFcn<U> | UnaryMapFcn<U> | BinaryMapFcn<U> | TernaryMapFcn<U>;
 
 /**
 * Reducer function invoked for each element in an array.
@@ -260,7 +260,7 @@
 * @param arr - array on which the method was called
 * @returns accumulated result
 */
 type Reducer<U> = NullaryReducer<U> | UnaryReducer<U> | BinaryReducer<U> | TernaryReducer<U> | QuaternaryReducer<U>;
 
 /**
 * Comparator function.
@@ -269,7 +269,7 @@
 * @param b - second value for comparison
 * @returns number indicating comparison result
 */
 type CompareFcn = ( a: Uint64, b: Uint64 ) => number;
 
 /**
 * Class for creating a 64-bit unsigned integer array.
@@ -426,6 +426,25 @@
 	*/
 	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 => <Uint64Array>[ 1n, 2n, 1n, 2n ]
+	*/
+	copyWithin( target: number, start: number, end?: number ): Uint64Array;
+
 	/**
 	* Returns an iterator for iterating over array key-value pairs.
 	*

lib/node_modules/@stdlib/array/uint64/lib/main.js

@@ -597,6 +597,40 @@
 */
 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 => <Uint64Array>[ 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.
 *
@@ -839,7 +873,7 @@
 		buf[ idx+indices.LOW ] = words[ 1 ];
 		return;
 	}
 	if ( isNonNegativeInteger( value ) || ( isBigInt( value ) && isNonNegativeInteger( Number( value ) ) ) ) {
 		if ( idx >= this._length ) {
 			throw new RangeError( format( 'invalid argument. Index argument is out-of-bounds. Value: `%u`.', idx ) );
 		}