File cleaner

Things to learn - Doing two async operations one after another

const fs = require('fs').promises;

async function cleanFile(filename) {
    try {
        // Read the file
        const content = await fs.readFile(filename, 'utf8');
        
        // Remove extra spaces
        const cleanedContent = content.replace(/\\s+/g, ' ').trim();
        
        // Write back to the same file
        await fs.writeFile(filename, cleanedContent);
        
        console.log(`File '${filename}' has been cleaned.`);
    } catch (error) {
        console.error('Error:', error.message);
    }
}

// Usage
const filename = 'a.txt';
cleanFile(filename);

Clock

Things to learn -

1. Optional arguments
2. Terenary operator

function formatTime(date, use24Hour = true) {
    const hours = use24Hour ? date.getHours() : (date.getHours() % 12 || 12);
    const minutes = date.getMinutes().toString().padStart(2, '0');
    const seconds = date.getSeconds().toString().padStart(2, '0');
    const ampm = use24Hour ? '' : (date.getHours() >= 12 ? 'PM' : 'AM');
    
    return `${hours.toString().padStart(2, '0')}:${minutes}:${seconds}${ampm ? ' ' + ampm : ''}`;
}

function displayTime() {
    const now = new Date();
    const time24 = formatTime(now);
    const time12 = formatTime(now, false);
    
    console.clear();
    console.log(`24-hour format: ${time24}`);
    console.log(`12-hour format: ${time12}`);
}

function startClock() {
    displayTime();
    setInterval(displayTime, 1000);
}

startClock();

console.log("Press Ctrl+C to stop the clock.");