Remove the first character(s) of a string.
npm install @stdlib/string-remove-first
Alternatively,
- To load the package in a website via a
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tag without installation and bundlers, use the ES Module available on theesm
branch. - If you are using Deno, visit the
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branch. - For use in Observable, or in browser/node environments, use the Universal Module Definition (UMD) build available on the
umd
branch. - To use as a general utility for the command line, install the corresponding CLI package globally.
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var removeFirst = require( '@stdlib/string-remove-first' );
Removes the first character(s) of a string
.
var out = removeFirst( 'last man standing' );
// returns 'ast man standing'
out = removeFirst( 'Hidden Treasures' );
// returns 'idden Treasures'
The function supports the following options:
-
mode: type of characters to return. Must be one of the following:
'grapheme'
: grapheme clusters. Appropriate for strings containing visual characters which can span multiple Unicode code points (e.g., emoji).'code_point'
: Unicode code points. Appropriate for strings containing visual characters which are comprised of more than one Unicode code unit (e.g., ideographic symbols and punctuation and mathematical alphanumerics).'code_unit'
: UTF-16 code units. Appropriate for strings containing visual characters drawn from the basic multilingual plane (BMP) (e.g., common characters, such as those from the Latin, Greek, and Cyrillic alphabets).
Default:
'grapheme'
.
By default, the function returns the first character. To return the first n
characters, provide a second argument specifying the number of characters to return.
var out = removeFirst( 'foo bar', 4 );
// returns 'bar'
out = removeFirst( 'foo bar', 10 );
// returns ''
- By default, the function assumes the general case in which an input string may contain an arbitrary number of grapheme clusters. This assumption comes with a performance cost. Accordingly, if an input string is known to only contain visual characters of a particular type (e.g., only alphanumeric), one can achieve better performance by specifying the appropriate
mode
option.
var removeFirst = require( '@stdlib/string-remove-first' );
var str = removeFirst( 'last man standing' );
// returns 'ast man standing'
str = removeFirst( 'presidential election' );
// returns 'residential election'
str = removeFirst( 'JavaScript' );
// returns 'avaScript'
str = removeFirst( 'Hidden Treasures' );
// returns 'idden Treasures'
str = removeFirst( 'The Last of the Mohicans', 4 );
// returns 'Last of the Mohicans'
str = removeFirst( '๐ถ๐ฎ๐ท๐ฐ๐ธ', 2 );
// returns '๐ท๐ฐ๐ธ'
str = removeFirst( '๐ถ๐ฎ๐ท๐ฐ๐ธ', 10 );
// returns ''
To use as a general utility, install the CLI package globally
npm install -g @stdlib/string-remove-first-cli
Usage: remove-first [options] [<string>]
Options:
-h, --help Print this message.
-V, --version Print the package version.
--n Number of characters to remove. Default: 1.
--split sep Delimiter for stdin data. Default: '/\\r?\\n/'.
--mode mode Type of character to return. Default: 'grapheme'.
-
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 $'beep\nboop' | remove-first --split /\r?\n/ # Escaped... $ echo -n $'beep\nboop' | remove-first --split /\\r?\\n/
-
The implementation ignores trailing delimiters.
$ remove-first beep
eep
To use as a standard stream,
$ echo -n 'beep\nboop' | remove-first --n=2
be
bo
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' | remove-first --split '\t'
eep
oop
@stdlib/string-remove-last
: remove the last character of a string.
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.
See LICENSE.
Copyright ยฉ 2016-2023. The Stdlib Authors.