@stdlib/string-code-point-at

Return a Unicode code point from a string at a specified position.

Usage no npm install needed!

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README

codePointAt

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Return a Unicode code point from a string at a specified position.

Installation

npm install @stdlib/string-code-point-at

Usage

var codePointAt = require( '@stdlib/string-code-point-at' );

codePointAt( string, position[, backward] )

Returns a Unicode code point from a string at a specified position.

var out = codePointAt( 'last man standing', 4 );
// returns 32

The function supports providing a boolean argument for performing backward iteration for low surrogates.

var out = codePointAt( '๐ŸŒท', 1, true );
// returns 127799

Notes

This function differs from String.prototype.codePointAt in the following ways:

  • The function supports providing a boolean argument for performing backward iteration for low surrogates. String.prototype.codePointAt simply returns the low surrogate value if no UTF-16 surrogate pair begins at the specified position. If invoked with backward set to true, this function will return the code point after aggregating with the preceding high surrogate, if the specified position does not mark the start of a surrogate pair.

Examples

var codePointAt = require( '@stdlib/string-code-point-at' );

console.log( codePointAt( 'last man standing', 4 ) );
// => 32

console.log( codePointAt( 'presidential election', 8, true ) );
// => 116

console.log( codePointAt( 'เค…เคจเฅเคšเฅเค›เฅ‡เคฆ', 2 ) );
// => 2369

console.log( codePointAt( '๐ŸŒท', 1, true ) );
// => 127799

CLI

Installation

To use the module as a general utility, install the module globally

npm install -g @stdlib/string-code-point-at

Usage

Usage: code-point-at [options] [<string>] --pos=<index>

Options:

  -h,    --help                Print this message.
  -V,    --version             Print the package version.
  -b,    --backward            Backward iteration for low surrogates.
         --pos index           Position in string.

Examples

$ code-point-at --pos=2 เค…เคจเฅเคšเฅเค›เฅ‡เคฆ
2369

To use as a standard stream,

$ echo -n 'เค…เคจเฅเคšเฅเค›เฅ‡เคฆ' | code-point-at --pos=2
2369

See Also

Notice

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

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License

See LICENSE.

Copyright

Copyright © 2016-2022. The Stdlib Authors.