Upgrade JavaScript var to let/const for Safer Scoping

By: fyvo August 4, 2025 JavaScript

Description

Many old JavaScript projects still use var, which can lead to bugs due to its function-scoping. This update replaces var with let or const depending on usage, improving reliability and readability.

Original Code (Outdated)

var name = "John";
var age = 30;
if (true) {
    var age = 40;
}
console.log(age); // 40

Updated Code (Modern)

const name = "John";
let age = 30;
if (true) {
    let age = 40;
}
console.log(age); // 30

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