feat: add next-code-point-index string package

lib/node_modules/@stdlib/string/next-code-point/README.md

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+<!--
+
+@license Apache-2.0
+
+Copyright (c) 2023 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.
+
+-->
+
+# nextCodePoint
+
+> Return the next code point in a string after a specified position.
+
+<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
+
+<section class="intro">
+
+</section>
+
+<!-- /.intro -->
+
+<!-- Package usage documentation. -->
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var nextCodePoint = require( '@stdlib/string/next-code-point' );
+```
+
+#### nextCodePoint( string\[, fromIndex] )
+
+Returns the next code point in a string after a specified position.
+
+```javascript
+var out = nextCodePoint( 'last man standing' );
+// returns 1
+```
+
+By default, the function searches for a grapheme cluster starting from the first index. To specify an alternative starting search index, provide a `fromIndex` argument.
+
+```javascript
+var out = nextCodePoint( 'last man standing', 4 );
+// returns 5
+```
+
+</section>
+
+<!-- /.usage -->
+
+<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="notes">
+
+## Notes
+
+-   If `string` is an empty string, the function returns `-1` irrespective of `fromIndex`.
+-   If an code point does not exist after `fromIndex`, the function returns `-1`.
+-   Note that `fromIndex` does **not** refer to a visual character position, but to an index in the ordered sequence of [UTF-16][utf-16] code units.
+
+</section>
+
+<!-- /.notes -->
+
+<!-- Package usage examples. -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var nextCodePoint = require( '@stdlib/string/next-code-point' );
+
+var out = nextCodePoint( 'last man standing', 4 );
+// returns 5
+
+out = nextCodePoint( 'presidential election', 8 );
+// returns 9
+
+out = nextCodePoint( 'अनुच्छेद', 1 );
+// returns 2
+
+out = nextCodePoint( '🌷', 0 );
+// returns -1
+```
+
+</section>
+
+<!-- /.examples -->
+
+<!-- Section for describing a command-line interface. -->
+
+* * *
+
+<section class="cli">
+
+## CLI
+
+<!-- CLI usage documentation. -->
+
+<section class="usage">
+
+### Usage
+
+```text
+Usage: next-code-point [options] [<string>]
+
+Options:
+
+  -h,    --help                Print this message.
+  -V,    --version             Print the package version.
+         --from index          Starting search position in string. Default: 0.
+```
+
+</section>
+
+<!-- /.usage -->
+
+<!-- CLI usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="notes">
+
+</section>
+
+<!-- /.notes -->
+
+<!-- CLI usage examples. -->
+
+<section class="examples">
+
+### Examples
+
+```bash
+$ next-code-point --from=1 अनुच्छेद
+3
+```
+
+To use as a [standard stream][standard-streams],
+
+```bash
+$ echo -n 'अनुच्छेद' | next-code-point --from=1
+3
+```
+
+</section>
+
+<!-- /.examples -->
+
+</section>
+
+<!-- /.cli -->
+
+<!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="references">
+
+</section>
+
+<!-- /.references -->
+
+<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
+
+<section class="related">
+
+* * *
+
+## See Also
+
+-   <span class="package-name">[`@stdlib/string/num-grapheme-clusters`][@stdlib/string/num-grapheme-clusters]</span><span class="delimiter">: </span><span class="description">return the number of grapheme clusters in a string.</span>
+
+</section>
+
+<!-- /.related -->
+
+<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="links">
+
+[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams
+
+[utf-16]: https://en.wikipedia.org/wiki/UTF-16
+
+<!-- <related-links> -->
+
+[@stdlib/string/num-grapheme-clusters]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/string/num-grapheme-clusters
+
+<!-- </related-links> -->
+
+</section>
+
+<!-- /.links -->

lib/node_modules/@stdlib/string/next-code-point/benchmark/benchmark.js

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+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2023 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 isInteger = require( '@stdlib/assert/is-integer' ).isPrimitive;
+var pkg = require( './../package.json' ).name;
+var nextCodePoint = require( './../lib' );
+
+
+// MAIN //
+
+bench( pkg, function benchmark( b ) {
+	var strings;
+	var len;
+	var out;
+	var i;
+
+	strings = [
+		'last man standing',
+		'presidential election',
+		'अनुच्छेद',
+		'🌷',
+		'书/六書',
+		'เ❄︎நி',
+		'กิิก้้ก็็ก็็กิิก้้ก็็กิิก้้กิิก้้ก็็ก็็กิิก้้ก็็กิิก้้',
+		'書六/书六',
+		'ܶƔλʃݖͱšɕ҆ʧѸؐҜҦɳΏ',
+		'âݝΝ‚ҳӌݾҀƳ۵ۧ޳ǁǸΓ'
+	];
+	len = strings.length;
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = nextCodePoint( strings[ i%len ], 1 );
+		if ( out !== out ) {
+			b.fail( 'should not return NaN' );
+		}
+	}
+	b.toc();
+	if ( !isInteger( out ) ) {
+		b.fail( 'should return an integer' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});

lib/node_modules/@stdlib/string/next-code-point/bin/cli

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+#!/usr/bin/env node
+
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2023 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 resolve = require( 'path' ).resolve;
+var readFileSync = require( '@stdlib/fs/read-file' ).sync;
+var CLI = require( '@stdlib/cli/ctor' );
+var stdin = require( '@stdlib/process/read-stdin' );
+var stdinStream = require( '@stdlib/streams/node/stdin' );
+var nextCodePoint = require( './../lib' );
+
+
+// MAIN //
+
+/**
+* Main execution sequence.
+*
+* @private
+* @returns {void}
+*/
+function main() {
+	var flags;
+	var args;
+	var cli;
+	var pos;
+
+	// Create a command-line interface:
+	cli = new CLI({
+		'pkg': require( './../package.json' ),
+		'options': require( './../etc/cli_opts.json' ),
+		'help': readFileSync( resolve( __dirname, '..', 'docs', 'usage.txt' ), {
+			'encoding': 'utf8'
+		})
+	});
+
+	// Get any provided command-line options:
+	flags = cli.flags();
+	if ( flags.help || flags.version ) {
+		return;
+	}
+	if ( flags.from ) {
+		pos = parseInt( flags.from, 10 );
+	} else {
+		pos = 0;
+	}
+	// Get any provided command-line arguments:
+	args = cli.args();
+
+	// Check if we are receiving data from `stdin`...
+	if ( stdinStream.isTTY ) {
+		return console.log( nextCodePoint( args[ 0 ], pos ) ); // eslint-disable-line no-console
+	}
+	return stdin( onRead );
+
+	/**
+	* Callback invoked upon reading from `stdin`.
+	*
+	* @private
+	* @param {(Error|null)} error - error object
+	* @param {Buffer} data - data
+	* @returns {void}
+	*/
+	function onRead( error, data ) {
+		if ( error ) {
+			return cli.error( error );
+		}
+		console.log( nextCodePoint( data.toString(), pos ) ); // eslint-disable-line no-console
+	}
+}
+
+main();

lib/node_modules/@stdlib/string/next-code-point/docs/repl.txt

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+
+{{alias}}( str[, fromIndex] )
+    Returns the next code point in a string after a specified position.
+
+    Parameters
+    ----------
+    str: string
+        Input string.
+
+    fromIndex: integer (optional)
+        Position. Default: 0.
+
+    Returns
+    -------
+    out: integer
+        Next code point position.
+
+    Examples
+    --------
+    > var out = {{alias}}( 'last man standing', 4 )
+    5
+    > out = {{alias}}( 'presidential election', 8 )
+    9
+    > out = {{alias}}( 'अनुच्छेद', 1 )
+    3
+    > out = {{alias}}( '🌷' )
+    -1
+
+    See Also
+    --------