stdlib-js / string-base-ends-with

Test if a string ends with the characters of another string.

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endsWith

Test if a string ends with the characters of another string.

Installation

npm install @stdlib/string-base-ends-with

Alternatively,

• To load the package in a website via a script tag without installation and bundlers, use the ES Module available on the esm branch (see README).
• If you are using Deno, visit the deno branch (see README for usage intructions).
• For use in Observable, or in browser/node environments, use the Universal Module Definition (UMD) build available on the umd branch (see README).

The branches.md file summarizes the available branches and displays a diagram illustrating their relationships.

To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.

Usage

var endsWith = require( '@stdlib/string-base-ends-with' );

endsWith( str, search, len )

Tests if a string ends with the characters of another string.

var str = 'Remember the story I used to tell you when you were a boy?';

var bool = endsWith( str, 'boy?', str.length );
// returns true

bool = endsWith( str, 'Boy?', str.length );
// returns false

To search from a specific character position, provide a len argument. If len is positive, the function restricts the search to a substring with length len, beginning with the leftmost character. If len is negative, len indicates to ignore the last len characters (equivalent to str.length + len).

var str = 'To be, or not to be, that is the question.';

var bool = endsWith( str, 'to be', 19 );
// returns true

bool = endsWith( str, 'to be', -23 );
// returns true

If provided an empty search string, the function always returns true.

var str = 'beep boop';

var bool = endsWith( str, '' );
// returns true

Notes

• In general, exercise caution when operating on substrings containing Unicode characters, as the visual character length may not equal the number of code points. For example,

  var len = '🏠'.length;
  // returns 2

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

  • The function assumes string values for the first and second arguments and assumes that the len argument is an integer value.
  • The function does not clamp positive len values to the end of the input string.
  • Except when provided an empty search string, the function always returns false if len resolves to a starting search position which exceeds the bounds of the input string.

Examples

var endsWith = require( '@stdlib/string-base-ends-with' );

var str = 'Fair is foul, and foul is fair, hover through fog and filthy air';

var bool = endsWith( str, 'air', str.length );
// returns true

bool = endsWith( str, 'fair', str.length );
// returns false

bool = endsWith( str, 'fair', 30 );
// returns true

bool = endsWith( str, 'fair', -34 );
// returns true

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See Also

• @stdlib/string-base/starts-with: test if a string starts with the characters of another string.

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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.

Community

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License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.