string-left-right

What is string-left-right?

The string-left-right npm package provides utilities for trimming whitespace from the left and right sides of strings, as well as other string manipulation functionalities.

What are string-left-right's main functionalities?

trimLeft

The trimLeft function removes whitespace from the left side of a string.

const { trimLeft } = require('string-left-right');
const result = trimLeft('   Hello World!   ');
console.log(result); // 'Hello World!   '

trimRight

The trimRight function removes whitespace from the right side of a string.

const { trimRight } = require('string-left-right');
const result = trimRight('   Hello World!   ');
console.log(result); // '   Hello World!'

trim

The trim function removes whitespace from both sides of a string.

const { trim } = require('string-left-right');
const result = trim('   Hello World!   ');
console.log(result); // 'Hello World!'

left

The left function returns the index of the first non-whitespace character from the left.

const { left } = require('string-left-right');
const result = left('   Hello World!   ');
console.log(result); // 3

right

The right function returns the index of the first non-whitespace character from the right.

const { right } = require('string-left-right');
const result = right('   Hello World!   ');
console.log(result); // 15

Other packages similar to string-left-right

lodash

Lodash is a popular utility library that provides a wide range of functions for manipulating arrays, objects, and strings. It includes functions like _.trim, _.trimStart, and _.trimEnd which are similar to the trim, trimLeft, and trimRight functions in string-left-right.

underscore

Underscore is another utility library similar to Lodash. It provides a variety of functions for working with arrays, objects, and strings. The _.trim function in Underscore is comparable to the trim function in string-left-right.

validator

Validator is a library for string validation and sanitization. It includes functions like trim, ltrim, and rtrim which are similar to the trim, trimLeft, and trimRight functions in string-left-right. However, Validator focuses more on validation and sanitization rather than general string manipulation.

README

string-left-right

Looks up the first non-whitespace character to the left/right of a given index

Install

This package is pure ESM. If you're not ready yet, install an older version of this program, 4.1.0 (npm i string-left-right@4.1.0).

npm i string-left-right

Quick Take

import { strict as assert } from "assert";

import {
  left,
  right,
  leftSeq,
  rightSeq,
  chompLeft,
  chompRight,
  leftStopAtNewLines,
  rightStopAtNewLines,
} from "string-left-right";

// get the closest non-whitespace character to the left of "d" (which itself
// is at string index 6)
const str = "abc   def";
//             |   |
//           012345678

assert.equal(
  `next non-whitespace character to the left of ${str[6]} (index 6) is ${
    str[left(str, 6)]
  } (index ${left(str, 6)})`,
  "next non-whitespace character to the left of d (index 6) is c (index 2)",
);

Documentation

Please visit codsen.com for a full description of the API.

Contributing

To report bugs or request features or assistance, raise an issue on GitHub.

Licence

MIT License.

Copyright © 2010-2025 Roy Revelt and other contributors.