@stdlib/string-substring-before-last

Return the part of a string before the last occurrence of a specified substring.

Usage no npm install needed!

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README

substringBeforeLast

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Return the part of a string before the last occurrence of a specified substring.

Installation

npm install @stdlib/string-substring-before-last

Usage

var substringBeforeLast = require( '@stdlib/string-substring-before-last' );

substringBeforeLast( str, search )

Returns the part of a string before the last occurrence of a specified substring.

var str = 'Beep Boop Beep';
var out = substringBeforeLast( str, 'Beep' );
// returns 'Beep Boop '

out = substringBeforeLast( str, 'Boop' );
// returns 'Beep '

Notes

  • If a substring is not present in a provided string, the function returns the input string.
  • If provided an empty substring, the function returns the input string.

Examples

var substringBeforeLast = require( '@stdlib/string-substring-before-last' );

var str = 'beep boop';
var out = substringBeforeLast( str, ' ' );
// returns 'beep'

out = substringBeforeLast( str, 'e' );
// returns 'be'

out = substringBeforeLast( str, 'x' );
// returns 'beep boop'

out = substringBeforeLast( str, '' );
// returns 'beep boop'

CLI

Installation

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

npm install -g @stdlib/string-substring-before-last

Usage

Usage: substring-before-last [options] --search=<string> [<string>]

Options:

  -h,    --help                Print this message.
  -V,    --version             Print the package version.
         --search string       Search string.
         --split sep           Delimiter for stdin data. Default: '/\\r?\\n/'.

Notes

  • If the split separator is a regular expression, ensure that the split option is either properly escaped or enclosed in quotes.

    # Not escaped...
$ echo -n 

foo\nbar\nbaz' | substring-before-last --search a --split /\r?\n/

# Escaped...
$ echo -n 

foo\nbar\nbaz' | substring-before-last --search a --split /\\r?\\n/

  • The implementation ignores trailing delimiters.

Examples

$ substring-before-last abcdefg --search d
abc

To use as a standard stream,

$ echo -n 

beep\nboop' | substring-before-last --search p
bee
boo

By default, when used as a standard stream, the implementation assumes newline-delimited data. To specify an alternative delimiter, set the split option.

$ echo -n 'beep\tboop' | substring-before-last --search p --split '\t'
bee
boo

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.

Community

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License

See LICENSE.

Copyright

Copyright © 2016-2022. The Stdlib Authors.