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Return the part of a string before the last occurrence of a specified substring.
import substringBeforeLast from 'https://cdn.jsdelivr.net/gh/stdlib-js/string-substring-before-last@deno/mod.js';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 '- 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.
import substringBeforeLast from 'https://cdn.jsdelivr.net/gh/stdlib-js/string-substring-before-last@deno/mod.js';
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'@stdlib/string-substring-before: return the part of a string before a specified substring.@stdlib/string-substring-after: return the part of a string after a specified substring.@stdlib/string-substring-after-last: return the part of a string after the last occurrence of a specified substring.
This package is part of stdlib, a standard library 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.
See LICENSE.
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