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Safae Beytour
Safae Beytour

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JavaScript vs. TypeScript⚡️

We all love JavaScript's flexibility, but we’ve all felt the pain of a crash in production. Is it time to switch?.

The Main Difference:

JavaScript (Dynamic): It's like writing an essay in a notebook. You won't know you made a spelling mistake until someone reads it.

TypeScript (Static): It's like writing in Word with spell-check on. It yells at you while you type if you make a mistake.

The Code Example:

The same bug in both languages. Notice the difference?

  1. JavaScript (Fails Silently ❌) JS lets you make mistakes and only crashes when the user runs the app.

JavaScript

function welcome(user) {
  // Bug: We accessed .age, but passed an object without it!
  console.log("Hello " + user.name + ", age " + user.age); 
}

welcome({ name: "Dev" }); 
// Output: "Hello Dev, age undefined" (Awkward...)
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  1. TypeScript (Catches Bugs Immediately ✅) TS stops you before you even save the file.

TypeScript

interface User {
  name: string;
  age: number;
}

function welcome(user: User) {
  console.log(`Hello ${user.name}, age ${user.age}`);
}

// Error in Editor: Property 'age' is missing! 
welcome({ name: "Dev" }); 

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Pros & Cons:

JavaScript: Setup is instant, but debugging is harder.

TypeScript: Setup takes a minute, but maintenance is 10x easier.

If you are building a small hobby project --> Stick with JS. If you are building a professional app with a team --> TS is non-negotiable in 2025.

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