String Utils JS

A comprehensive collection of utility functions for string manipulation, including trimming, casing, formatting, validation, transformation, HTML escaping, random string generation, and more. These utilities are designed to simplify common string operations and are used across the System Designer Core module.

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Features

• Trimming & Whitespace: Trim, remove, or replace whitespace.
• Casing: Convert to upper, lower, camel, kebab, snake, and title case.
• Formatting: Truncate, pad, repeat, join, and replace substrings.
• Validation: Check for empty strings, prefixes, and suffixes.
• Transformation: Reverse, capitalize, remove duplicates, and split strings.
• HTML Utilities: Escape and unescape HTML characters, strip HTML tags.
• Random String Generation: Generate random strings with customizable character sets.
• Slugify: Convert strings into URL-friendly slugs.
• Pluralization: Pluralize and singularize English nouns.

Installation

npm install @js-utility/string

API & Use Cases

Trimming & Whitespace

trim(str)

Removes whitespace from both ends.

import { trim } from '@js-utility/string';
trim('   Hello World!   '); // 'Hello World!'

removeWhitespace(str)

Removes all whitespace.

import { removeWhitespace } from '@js-utility/string';
removeWhitespace('  a b  c d '); // 'abcd'

replaceMultipleSpaces(str)

Replaces multiple spaces with a single space.

import { replaceMultipleSpaces } from '@js-utility/string';
replaceMultipleSpaces('a   b    c'); // 'a b c'

Casing

upper(str)

Converts to uppercase.

import { upper } from '@js-utility/string';
upper('hello'); // 'HELLO'

lower(str)

Converts to lowercase.

import { lower } from '@js-utility/string';
lower('HELLO'); // 'hello'

capitalize(str)

Capitalizes the first letter.

import { capitalize } from '@js-utility/string';
capitalize('hello world'); // 'Hello world'

capitalizeEachWord(str)

Capitalizes the first letter of each word.

import { capitalizeEachWord } from '@js-utility/string';
capitalizeEachWord('hello world'); // 'Hello World'

camelCase(str)

Converts to camelCase.

import { camelCase } from '@js-utility/string';
camelCase('hello world example'); // 'helloWorldExample'

kebabCase(str)

Converts to kebab-case.

import { kebabCase } from '@js-utility/string';
kebabCase('Hello World Example'); // 'hello-world-example'

snakeCase(str)

Converts to snake_case.

import { snakeCase } from '@js-utility/string';
snakeCase('Hello World Example'); // 'hello_world_example'

titleCase(str)

Converts to Title Case.

import { titleCase } from '@js-utility/string';
titleCase('hello world example'); // 'Hello World Example'

Formatting

truncate(str, maxLength)

Truncates a string and adds ellipsis if needed.

import { truncate } from '@js-utility/string';
truncate('Hello World', 5); // 'He...'

padLeft(str, targetLength, padChar?)

Pads string on the left.

import { padLeft } from '@js-utility/string';
padLeft('42', 5, '0'); // '00042'

padRight(str, targetLength, padChar?)

Pads string on the right.

import { padRight } from '@js-utility/string';
padRight('42', 5, '0'); // '42000'

padBoth(str, targetLength, padChar?)

Pads string on both sides.

import { padBoth } from '@js-utility/string';
padBoth('42', 6, '*'); // '**42**'

repeat(str, count)

Repeats a string.

import { repeat } from '@js-utility/string';
repeat('ab', 3); // 'ababab'

replaceAll(str, search, replacement)

Replaces all occurrences of a substring.

import { replaceAll } from '@js-utility/string';
replaceAll('foo bar foo', 'foo', 'baz'); // 'baz bar baz'

joinStrings(separator, ...parts)

Joins multiple strings with a separator.

import { joinStrings } from '@js-utility/string';
joinStrings('-', 'a', 'b', 'c'); // 'a-b-c'

Validation

isEmptyStr(str)

Checks if a string is empty or whitespace.

import { isEmptyStr } from '@js-utility/string';
isEmptyStr('   '); // true

startsWith(str, prefix)

Checks if string starts with prefix.

import { startsWith } from '@js-utility/string';
startsWith('Hello', 'He'); // true

endsWith(str, suffix)

Checks if string ends with suffix.

import { endsWith } from '@js-utility/string';
endsWith('Hello', 'lo'); // true

Transformation

reverse(str)

Reverses a string.

import { reverse } from '@js-utility/string';
reverse('abc'); // 'cba'

split(str, delimiter)

Splits a string by delimiter.

import { split } from '@js-utility/string';
split('a,b,c', ','); // ['a', 'b', 'c']

charAt(str, index)

Gets character at index.

import { charAt } from '@js-utility/string';
charAt('hello', 1); // 'e'

toCharArray(str)

Converts string to array of characters.

import { toCharArray } from '@js-utility/string';
toCharArray('abc'); // ['a', 'b', 'c']

removeDuplicateChars(str)

Removes duplicate characters.

import { removeDuplicateChars } from '@js-utility/string';
removeDuplicateChars('aabbcc'); // 'abc'

removeDuplicateWords(str)

Removes duplicate words.

import { removeDuplicateWords } from '@js-utility/string';
removeDuplicateWords('foo bar foo baz'); // 'foo bar baz'

removeConsecutiveDuplicates(str)

Removes consecutive duplicate characters.

import { removeConsecutiveDuplicates } from '@js-utility/string';
removeConsecutiveDuplicates('aaabbbcc'); // 'abc'

removeConsecutiveDuplicateWords(str)

Removes consecutive duplicate words.

import { removeConsecutiveDuplicateWords } from '@js-utility/string';
removeConsecutiveDuplicateWords('foo foo bar bar bar baz'); // 'foo bar baz'

HTML Utilities

escapeHtml(str)

Escapes special HTML characters.

import { escapeHtml } from '@js-utility/string';
escapeHtml('<div>"Hello"</div>'); // '&lt;div&gt;&quot;Hello&quot;&lt;/div&gt;'

unescapeHtml(str)

Unescapes HTML entities.

import { unescapeHtml } from '@js-utility/string';
unescapeHtml('&lt;div&gt;Hello&lt;/div&gt;'); // '<div>Hello</div>'

stripHtmlTags(str)

Removes HTML tags.

import { stripHtmlTags } from '@js-utility/string';
stripHtmlTags('<b>Hello</b> World'); // 'Hello World'

Random String Generation

random(length?, type?)

Generates a random string.
Types: "upper", "lower", "alpha", "number", "alphanumeric", "special", "mix" (default).

import { random } from '@js-utility/string';
random(8, 'alpha'); // e.g. 'aBcDeFgH'
random(10, 'number'); // e.g. '4839201745'

Slugify

slugify(str)

Converts to a URL-friendly slug.

import { slugify } from '@js-utility/string';
slugify('Hello World!'); // 'hello-world'

Pluralization

pluralize(str)

Converts a singular noun to plural.

import { pluralize } from '@js-utility/string';
pluralize('child'); // 'children'

singularize(str)

Converts a plural noun to singular.

import { singularize } from '@js-utility/string';
singularize('children'); // 'child'

📘 TypeScript Support

This package is built with full TypeScript support. All functions are type-safe, and type definitions are bundled, so you get autocomplete, inline documentation, and compile-time safety out of the box, no need to install @types.

Examples :

import { deepMerge } from '@js-utility/object';

const result = deepMerge<{ a: number }, { b: string }>({ a: 1 }, { b: 'hello' });
// result is inferred as: { a: number; b: string }

🧪 Testing

This package is thoroughly tested using Jest, with a focus on correctness, edge cases, and null-safety.

🤝 Contributing

This project is maintained privately. While direct contributions (e.g., pull requests or code changes) are not open to the public, feedback, suggestions, and issue reports are always welcome.

If you notice any bugs, edge cases, or have ideas for improvement, feel free to reach out or open an issue (if access is available). Your input helps make the package more robust and useful for everyone!

💖 Support / Donate

If you find this package useful, consider supporting its development. Your support helps maintain the project, improve documentation, and add new features.

Support as through :

• Buy Me a Coffee ☕
• GitHub

💬 Support & Feedback

Have ideas, suggestions, or found a bug? I'd love to hear from you!

• Feedback: Whether it’s a feature request or an edge case you'd like handled, your input helps improve the package.
• Issues: If you run into a bug or unexpected behavior, feel free to open an issue (if the repo is accessible).
• Reach Out: You can also reach out directly for feedback or discussion via email or the contact details in the repository.

Your feedback helps shape better tools for everyone using this package.