quick refresher in typescript

To quickly refresh your knowledge in TypeScript, you can follow these steps:

1. Set up a development environment: Install Node.js and a code editor such as Visual Studio Code.

2. Install TypeScript: Open your terminal or command prompt and run the following command to install TypeScript globally:

   index.ts
   npm install -g typescript
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   2 lines

3. Create a TypeScript file: Create a new file with a .ts extension, for example app.ts. This file will contain your TypeScript code.

4. Write TypeScript code: TypeScript is a superset of JavaScript, so you can write JavaScript code directly in a TypeScript file. However, you can also take advantage of TypeScript's additional features such as static typing and interfaces. Here's an example of a simple TypeScript code snippet:

   index.ts
   function sayHello(name: string) {
     console.log(`Hello, ${name}!`);
   }
   
   let personName: string = "John";
   sayHello(personName);
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   7 lines

5. Compile TypeScript code: In the terminal or command prompt, navigate to the directory where your TypeScript file is located and run the following command to compile your TypeScript code into JavaScript:

   index.ts
   tsc app.ts
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   2 lines

   This will generate a new JavaScript file with the same filename and a .js extension, for example app.js.

6. Run the JavaScript code: Now you can run the generated JavaScript code using Node.js. In the terminal or command prompt, run the following command to execute your code:

   index.ts
   node app.js
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   You should see the output Hello, John! in the console.

This quick refresher should help you get started with TypeScript. Make sure to explore TypeScript's documentation and try out more advanced features to deepen your knowledge.