Common Helpers

General-purpose browser utility functions for clipboard, downloads, debouncing, cookies, and cache management.

Browser Only

All functions in this module require a browser environment (window, document, navigator). They will throw or be no-ops in Node.js/SSR contexts.

Installation

import { CommonHelpers } from '@igortrindade/lazyfy'
// or individually:
import { debounce, copyToClipboard, downloadRawData, getLetterByNumber, clearBrowserCache, clearBrowserCacheListener, removeAllCookies } from '@igortrindade/lazyfy'

---

debounce

Wraps a function so it only executes after timeout milliseconds have elapsed since the last call. Ideal for search inputs, resize handlers, and other high-frequency events.

Signature:

debounce<T extends (...args: any[]) => any>(callback: T, timeout?: number): (...args: Parameters<T>) => void

Parameter	Type	Default	Description
callback	Function	—	Function to debounce
timeout	number	300	Milliseconds to wait before calling

Examples:

const onSearch = CommonHelpers.debounce((query: string) => {
  fetchResults(query)
}, 500)

// Only calls fetchResults after 500ms of inactivity
inputElement.addEventListener('input', (e) => onSearch(e.target.value))

// With Vue
import { debounce } from '@igortrindade/lazyfy'

const handleInput = debounce((value: string) => {
  console.log('searching for:', value)
}, 300)

---

copyToClipboard

Copies a string to the user's clipboard. Uses the modern navigator.clipboard API with a fallback for older browsers.

Signature:

copyToClipboard(string: string): void

Examples:

CommonHelpers.copyToClipboard('https://github.com/igortrinidad/lazyfy')
// Text is now in the clipboard

---

downloadRawData

Triggers a file download in the browser with the provided string content.

Signature:

downloadRawData(data: string, fileName?: string): void

Parameter	Type	Default	Description
data	string	—	File content as a string
fileName	string	'file.txt'	Name of the downloaded file

Examples:

// Download a CSV
const csvContent = 'name,age\nAlice,30\nBob,25'
CommonHelpers.downloadRawData(csvContent, 'users.csv')

// Download a JSON file
const json = JSON.stringify({ version: '1.0.0' }, null, 2)
CommonHelpers.downloadRawData(json, 'config.json')

---

getLetterByNumber

Returns the lowercase letter corresponding to a zero-based index (0 → 'a', 1 → 'b', etc.). Returns '--' if the index is out of range.

Signature:

getLetterByNumber(number: number): string

Examples:

CommonHelpers.getLetterByNumber(0)   // 'a'
CommonHelpers.getLetterByNumber(1)   // 'b'
CommonHelpers.getLetterByNumber(25)  // 'z'
CommonHelpers.getLetterByNumber(26)  // '--'

Use case

Useful for generating labeled options in forms or quiz answers (a, b, c...).

---

removeAllCookies

Removes all browser cookies by setting their expiry date to the past.

Signature:

removeAllCookies(): void

Examples:

CommonHelpers.removeAllCookies()
// All cookies are now expired/removed

---

clearBrowserCache

Clears localStorage, sessionStorage, and optionally all cookies.

Signature:

clearBrowserCache(removeCookies?: boolean): void

Parameter	Type	Default	Description
removeCookies	boolean	true	Also remove all cookies

Examples:

CommonHelpers.clearBrowserCache()        // clears storage + cookies
CommonHelpers.clearBrowserCache(false)   // clears storage only

---

clearBrowserCacheListener

Attaches a keyboard shortcut listener that clears the browser cache when triggered (default: Alt + X). Optionally calls a callback or reloads the page.

Signature:

clearBrowserCacheListener(hotKey?: string, removeCookies?: boolean, cb?: Function | null): void

Parameter	Type	Default	Description
hotKey	string	'KeyX'	KeyboardEvent code value for the shortcut
removeCookies	boolean	true	Also remove cookies when triggered
cb	Function | null	null	Callback after clearing (if null, reloads the page)

Examples:

// Default: Alt+X clears cache and reloads
CommonHelpers.clearBrowserCacheListener()

// Custom key + callback
CommonHelpers.clearBrowserCacheListener('KeyR', true, () => {
  console.log('Cache cleared!')
  router.push('/')
})

Dev Utility

This is useful during development to quickly reset application state without opening DevTools.