📃 Table of Contents

• Features
• Usage
• API
• Examples
• Changelog
• Support
• License
• Related
• Author

🤖 Features

• 🔍 Flexible matching - check strings with full or partial match modes
• 🆎 Case‑sensitive or insensitive - choose the precision you need
• ⚡ Fast lookups - loops through entries efficiently for quick results
• 🎯 Custom comparators - plug in your own matching logic
• 🛡 Safe defaults - validates inputs before running comparisons
• 🧩 Reusable helpers - strIsIn for booleans, findMatch for actual matches
• 📦 Lightweight & dependency‑free - minimal footprint, maximum utility

🕵🏼 Usage

Install it by executing any of the following, depending on your preferred package manager:

pnpm add @igorskyflyer/str-is-in

yarn add @igorskyflyer/str-is-in

npm i @igorskyflyer/str-is-in

🤹🏼 API

ComparatorCallback

A type named ComparatorCallback is exposed and used as a signature for the comparator parameter of the strIsIn() function.

type ComparatorCallback = (entry: string, value: string) => boolean

strIsIn()

strIsIn(value: string, entries: string[], comparator?: ComparatorCallback): boolean

Checks whether the given String is present in the provided array of Strings.

findMatch

findMatch.full(value: string, entries: string[]): string

Performs a case-insensitive and full-matching search for a given value inside an array of values and returns the found match (with the original case being preserved). If none is found an empty string is returned.

findMatch.partial(value: string, entries: string[]): string

Performs a case-insensitive and partial-matching search for a given value inside an array of values and returns the found match (with the original case being preserved). If none is found an empty string is returned.

🗒️ Examples

import { strIsIn, findMatch } from '@igorskyflyer/str-is-in'

// #1 - use default Comparator, non-existent string, full match
console.log(strIsIn('bin', ['abc', 'cde', 'def', 'binary'])) // prints false

// #2 - use default Comparator, existing string, full match
console.log(strIsIn('bin', ['abc', 'cde', 'bin', 'adc'])) // prints true

// #3 - empty array passed
console.log(strIsIn('bin', [])) // prints false

// #4 - custom Comparator, partial match
console.log(strIsIn('bin', ['abc', 'cde', 'def', 'binary'], (entry, value) => entry.indexOf(value) > -1)) // prints true

// #5 - custom Comparator, partial match
console.log(strIsIn('bin', ['abc', 'cde', 'def', 'HellobinaryWorld'], (entry, value) => entry.indexOf(value) > -1)) // prints true

// #6 - custom Comparator, partial match, non-existent string
console.log(
  strIsIn('t', ['abc', 'cde', 'def', 'HellobinaryWorld'], (entry, value) => entry.toLowerCase() === value.toLowerCase())
) // prints false

// #7 - custom Comparator, partial match, existing string, case-insensitive
console.log(strIsIn('WORLD', ['abc', 'cde', 'def', 'world'], (entry, value) => entry.toLowerCase() === value.toLowerCase())) // prints true

// #8 - custom Comparator, partial match, case-insensitive
console.log(
  strIsIn(
    'WORLD',
    ['abc', 'cde', 'def', 'HellobinaryWorld'],
    (entry, value) => entry.toLowerCase().indexOf(value.toLowerCase()) > -1
  )
) // prints true

// #9 - full match-finding
console.log(findMatch.full('WORLD', ['abc', 'cde', 'world', 'HellobinaryWorld'])) // prints 'world'

// #10 - partial match-finding
console.log(findMatch.partial('WORLD', ['abc', 'cde', 'world-foo', 'HellobinaryWorld'])) // prints 'world-foo'

📝 Changelog

📑 The changelog is available here, CHANGELOG.md.

🪪 License

Licensed under the MIT license which is available here, MIT license.

💖 Support

🧬 Related

@igorskyflyer/pathexists

🧲 Provides ways of properly checking if a path exists inside a given array of files/directories both on Windows and UNIX-like operating systems. 🗺

@igorskyflyer/valid-path

🧰 Provides ways of testing whether a given value can be a valid file/directory name. 🏜

@igorskyflyer/regkeys

📚 An NPM package for fetching Windows registry keys. 🗝

@igorskyflyer/extendable-string

🦀 ExtendableString allows you to create strings on steroids that have custom transformations applied to them, unlike common, plain strings. 🪀

@igorskyflyer/normalized-string

💊 NormalizedString provides you with a String type with consistent line-endings, guaranteed. 📮

👨🏻‍💻 Author

Created by Igor Dimitrijević (@igorskyflyer).