Left Pad

Left pad a string.

Installation

$ npm install utils-left-pad-string

Usage

var lpad = require( 'utils-left-pad-string' );

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' );
  // returns 'beepbeepboop' => length 12
  
  str = str.substring( str.length-10 );
  // returns 'epbeepboop' => length 10

Examples

var round = require( 'math-round' );
var lpad = require( 'utils-left-pad-string' );

var str = 'beep';
var n;
var i;

for ( i = 0; i < 100; i++ ) {
	n = round( Math.random()*10 ) + str.length;
	console.log( lpad( str, n, 'b' ) );
}

To run the example code from the top-level application directory,

$ node ./examples/index.js

CLI

Installation

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

$ npm install -g utils-left-pad-string

Usage

Usage: lpad [options] str --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: ' '.

Examples

$ lpad beep --len 10 --pad b
# => bbbbbbbeep

Tests

Unit

This repository uses tape for unit tests. To run the tests, execute the following command in the top-level application directory:

$ make test

All new feature development should have corresponding unit tests to validate correct functionality.

Test Coverage

This repository uses Istanbul as its code coverage tool. To generate a test coverage report, execute the following command in the top-level application directory:

$ make test-cov

Istanbul creates a ./reports/coverage directory. To access an HTML version of the report,

$ make view-cov

Browser Support

This repository uses Testling for browser testing. To run the tests in a (headless) local web browser, execute the following command in the top-level application directory:

$ make test-browsers

To view the tests in a local web browser,

$ make view-browser-tests

License

MIT license.

Copyright

Copyright © 2016. Athan Reines.