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rpad

Right pad a string.

Installation

npm install @stdlib/string-base-right-pad

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 rpad = require( '@stdlib/string-base-right-pad' );

rpad( str, len, pad )

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

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

str = rpad( 'beep', 10, 'b' );
// returns 'beepbbbbbb'

str = rpad( 'boop', 12, 'beep' );
// returns 'boopbeepbeep'

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 = rpad( 'boop', 10, 'beep' ); // => length 12
  // returns 'boopbeepbeep'
  
  str = str.substring( 0, 10 ); // => length 10
  // returns 'boopbeepbe'
  
  str = str.substring( str.length-10 ); // => length 10
  // returns 'opbeepbeep'

Examples

var discreteUniform = require( '@stdlib/random-array-discrete-uniform' );
var papply = require( '@stdlib/utils-papply' );
var papplyRight = require( '@stdlib/utils-papply-right' );
var naryFunction = require( '@stdlib/utils-nary-function' );
var map = require( '@stdlib/utils-map' );
var logEach = require( '@stdlib/console-log-each' );
var rpad = require( '@stdlib/string-base-right-pad' );

// Define a string to pad:
var str = 'beep';

// Generate random lengths:
var lens = discreteUniform( 10, str.length, str.length+10 );

// Create a function for creating padded strings:
var fcn = naryFunction( papply( papplyRight( rpad, 'b' ), str ), 1 );

// Generate padded strings:
var out = map( lens, fcn );

// Print results:
logEach( '%s', out );

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See Also

• @stdlib/string-base/left-pad: left pad a 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 © 2016-2025. The Stdlib Authors.