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Sequential Queue

0 likes • Feb 6, 2021 • 2 views
JavaScript
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React - Lifting State

CHS
0 likes • Jan 25, 2023 • 0 views
JavaScript
export const Main = () => {
const [title, setTitle] = useState('');
return (
<ChildComponent
title={title}
onChange={e => setTitle(e.target.value)}
/>
);
};
export const ChildComponent = ({ title, onChange }) => {
return (
<Box component="form" onSubmit={() => {}} noValidate mt={5}>
<TextField
fullWidth
id="title"
label="Title"
name="title"
autoComplete="title"
autoFocus
color="primary"
variant="filled"
InputLabelProps={{ shrink: true }}
value={title}
onChange={onChange}
/>
</Box>
);
};

Flatten an array

0 likes • Nov 19, 2022 • 0 views
JavaScript
const flat = arr => [].concat.apply([], arr.map(a => Array.isArray(a) ? flat(a) : a));
// Or
const flat = arr => arr.reduce((a, b) => Array.isArray(b) ? [...a, ...flat(b)] : [...a, b], []);
// Or
// See the browser compatibility at https://caniuse.com/#feat=array-flat
const flat = arr => arr.flat();
// Example
flat(['cat', ['lion', 'tiger']]); // ['cat', 'lion', 'tiger']

hamming distance

0 likes • Nov 19, 2022 • 0 views
JavaScript
const hammingDistance = (num1, num2) =>
((num1 ^ num2).toString(2).match(/1/g) || '').length;
hammingDistance(2, 3); // 1

geometric progression

0 likes • Nov 19, 2022 • 0 views
JavaScript
const geometricProgression = (end, start = 1, step = 2) =>
Array.from({
length: Math.floor(Math.log(end / start) / Math.log(step)) + 1,
}).map((_, i) => start * step ** i);
geometricProgression(256); // [1, 2, 4, 8, 16, 32, 64, 128, 256]
geometricProgression(256, 3); // [3, 6, 12, 24, 48, 96, 192]
geometricProgression(256, 1, 4); // [1, 4, 16, 64, 256]

localStorage Cookie Consent

0 likes • Oct 9, 2023 • 43 views
JavaScript
import React, { useState, useEffect } from 'react';
import Link from 'next/link';
export default function CookieBanner() {
// Initialize with a default value (false if not previously set in localStorage)
const [cookieConsent, setCookieConsent] = useState(() =>
localStorage.getItem('cookieConsent') === 'true' ? true : false
);
useEffect(() => {
const newCookieConsent = cookieConsent ? 'granted' : 'denied';
window.gtag('consent', 'update', {
analytics_storage: newCookieConsent
});
localStorage.setItem('cookieConsent', String(cookieConsent));
}, [cookieConsent]);
return !cookieConsent && (
<div>
<div>
<p>
We use cookies to enhance the user experience.{' '}
<Link href='/privacy/'>View privacy policy</Link>
</p>
</div>
<div>
<button type="button" onClick={() => setCookieConsent(false)}>Decline</button>
<button type="button" onClick={() => setCookieConsent(true)}>Allow</button>
</div>
</div>
)
}

Check if array is empty

0 likes • Nov 19, 2022 • 0 views
JavaScript
arr = [] // empty array
const isEmpty = arr => !Array.isArray(arr) || arr.length === 0;
// Examples
isEmpty([]); // true
isEmpty([1, 2, 3]); // false