Nostalgic Pickled Mango

    @stdlib/string-left-pad
    TypeScript icon, indicating that this package has built-in type declarations

    0.0.8 • Public • Published

    Left Pad

    NPM version Build Status Coverage Status

    Left pad a string.

    Installation

    npm install @stdlib/string-left-pad

    Usage

    var lpad = require( '@stdlib/string-left-pad' );

    lpad( str, len[, pad] )

    Left pads a string such that the padded string has a length of at least len.

    var str = lpad( 'a', 5 );
    // returns '    a'

    By default, an input string is padded with spaces. To pad with a different character or sequence of characters, provide a pad string.

    var str = lpad( 'beep', 10, 'b' );
    // returns 'bbbbbbbeep'
    
    str = lpad( 'boop', 12, 'beep' );
    // returns 'beepbeepboop'

    Notes

    • An output string is not guaranteed to have a length of exactly len, but to have a length of at least len. To generate a padded string having a length equal to len

      var str = lpad( 'boop', 10, 'beep' ); // => length 12
      // returns 'beepbeepboop'
      
      str = str.substring( str.length-10 ); // => length 10
      // returns 'epbeepboop'

    Examples

    var round = require( '@stdlib/math-base-special-round' );
    var randu = require( '@stdlib/random-base-randu' );
    var lpad = require( '@stdlib/string-left-pad' );
    
    var str = 'beep';
    var n;
    var i;
    
    for ( i = 0; i < 100; i++ ) {
        n = round( randu()*10 ) + str.length;
        console.log( lpad( str, n, 'b' ) );
    }

    CLI

    Installation

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

    npm install -g @stdlib/string-left-pad

    Usage

    Usage: lpad [options] [<string>] --len=<length>
    
    Options:
    
      -h,    --help                Print this message.
      -V,    --version             Print the package version.
             --len length          Minimum string length.
             --pad str             String used to pad. Default: ' '.
             --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 $'beep\nboop' | lpad -len 8 --split /\r?\n/
      
      # Escaped...
      $ echo -n $'beep\nboop' | lpad -len 8 --split /\\r?\\n/
    • The implementation ignores trailing delimiters.

    Examples

    $ lpad beep --len 10 --pad b
    bbbbbbbeep

    To use as a standard stream,

    $ echo -n 'beep' | lpad --len 8
        beep

    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 'boop\tbeep' |  lpad --len 8 --split '\t'
        boop
        beep

    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

    Chat


    License

    See LICENSE.

    Copyright

    Copyright © 2016-2022. The Stdlib Authors.

    Install

    npm i @stdlib/string-left-pad

    Homepage

    stdlib.io

    DownloadsWeekly Downloads

    278

    Version

    0.0.8

    License

    Apache-2.0

    Unpacked Size

    45.4 kB

    Total Files

    12

    Last publish

    Collaborators

    • stdlib-bot
    • kgryte
    • planeshifter
    • rreusser