Master JavaScript: 10 Surprising One-Liners You Need to Know 🚀 | by Lokesh Prajapati | Feb, 2025

JavaScript is stuffed with surprises, and mastering one-liners can stage up your coding sport! Listed here are 10 contemporary JavaScript one-liners that may make your code extra environment friendly and readable. Prepare so as to add some magic to your scripts! ✨

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Define:

1️⃣ Convert an Object to Question String Parameters 🌐
2️⃣ Discover the Most Worth in an Array 🔝
3️⃣ Convert a Quantity to a Comma-Separated Format 💰
4️⃣ Examine if a 12 months is a Leap 12 months 📆
5️⃣ Convert a String to Title Case 🔠
6️⃣ Get the Present Timestamp in Seconds ⏳
7️⃣ Merge Two Arrays With out Duplicates 🔗
8️⃣ Get the File Extension from a Filename 📁
9️⃣ Get the Common of an Array of Numbers 📊
🔟 Discover the First Repeating Character in a String 🔄

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1️⃣ Convert an Object to Question String Paramet

✅ Good for working with APIs and URL parameters.

const toQueryString = (obj) => new URLSearchParams(obj).toString();
console.log(toQueryString({ identify: 'John', age: 30 })); // "identify=John&age=30"

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2️⃣ Discover the Most Worth in an Array 🔝

✅ Ensures the enter is a non-empty array earlier than discovering the utmost worth.

const maxVal = (arr) => Array.isArray(arr) && arr.size ? Math.max(...arr) : undefined;
console.log(maxVal([10, 5, 100, 2])); // 100
console.log(maxVal([])); // undefined
console.log(maxVal("hey")); // undefined

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3️⃣ Convert a Quantity to a Comma-Separated Format 💰

✅ Nice for displaying massive numbers in a readable format.

const formatNumber = (num) => num.toLocaleString();
console.log(formatNumber(1000000)); // "1,000,000"

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4️⃣ Examine if a 12 months is a Leap 12 months 📆

✅ Helps decide leap years with easy logic.

const isLeapYear = (12 months) => 12 months % 4 === 0 && (12 months % 100 !== 0 || 12 months % 400 === 0);
console.log(isLeapYear(2024)); // true

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5️⃣ Convert a String to Title Case 🔠

✅ Helpful for formatting textual content dynamically.

const toTitleCase = (str) => str.substitute(/bw/g, (char) => char.toUpperCase());
console.log(toTitleCase("hey world")); // "Hiya World"

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6️⃣ Get the Present Timestamp in Seconds ⏳

✅ Converts the present timestamp to seconds.

const getTimestamp = () => Math.flooring(Date.now() / 1000);
console.log(getTimestamp()); // 1740365707 (instance)

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7️⃣ Merge Two Arrays With out Duplicates 🔗

✅ Combines arrays and removes duplicates effortlessly.

const mergeUniqueArray = (arr1, arr2) => [...new Set([...arr1, ...arr2])];
console.log(mergeUniqueArray([1, 2, 3], [3, 4, 5])); // [1, 2, 3, 4, 5]

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8️⃣ Get the File Extension from a Filename 📁

✅ Shortly extracts the file sort from a filename.

const getFileExtension = filename => filename.slice((filename.lastIndexOf(".") - 1 >>> 0) + 2);
console.log(getFileExtension("doc.pdf")); // "pdf"
console.log(getFileExtension("archive.tar.gz")); // "gz"
console.log(getFileExtension(".gitignore")); // ""
console.log(getFileExtension("filename")); // ""

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9️⃣ Get the Common of an Array of Numbers 📊

✅ Calculates the common in a clear, concise manner.

const common = (arr) => arr.cut back((a, b) => a + b, 0) / arr.size;
console.log(common([10, 20, 30])); // 20

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🔟 Discover the First Repeating Character in a String 🔄

✅ Useful for detecting repeated characters in strings.

const firstRepeatingChar = (str) => str.break up('').discover((c, i, arr) => arr.indexOf(c) !== i);
console.log(firstRepeatingChar("javascript")); // "a"

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🚀 Last Ideas

These JavaScript one-liners make it easier to write cleaner and extra environment friendly code. By mastering these methods, you’ll code smarter, not tougher! 💡

💬 Which one did you discover most helpful? Let me know within the feedback! ⬇️