Roadmap

    2 - Exercise I

    Install TypeScript and Write a Simple TypeScript Program

    Objectives:

    • Set up a TypeScript development environment.
    • Write and run a simple TypeScript program.

    Steps:

    1. If you haven't already created a project directory, do so and navigate into it:

      bash
      mkdir typescript-basics
      cd typescript-basics

    2. Initialize a new Node.js project:

      bash
      npm init -y

    3. Install TypeScript as a local dependency:

      bash
      npm install typescript --save-dev

    4. Create a TypeScript configuration file:

      json
      // tsconfig.json
      {
        "compilerOptions": {
          "target": "es5",
          "module": "commonjs",
          "strict": true,
          "outDir": "./dist",
          "rootDir": "./src"
        },
        "exclude": ["node_modules"],
        "include": ["src"]
      }

    5. Create a src directory. This is where we will put our .ts typescript files.

      bash
      mkdir src

    6. Write a Simple TypeScript Program:

      • Create a new file named index.ts in the src directory.
      • Open index.ts in your text editor and add the following code:
      ts
      // index.ts
      // Define a variable with a string type
      ?? = "Hello, TypeScript!";
      // Define a function that returns a greeting message
      function greet(name: string){
          return `${greeting} Welcome, ${name}!`;
      }
      // Call the function and log the result
      console.log(greet("Student"));

    7. Compile the TypeScript Code:

      • Compile your TypeScript code to JavaScript using the TypeScript compiler. Run the following command in your terminal:
      bash
      npx tsc
      • This will generate a dist directory and a file named index.js inside it with our compiled code.

    8. Run the JavaScript Code:

      • Run the compiled JavaScript code using Node.js:
      bash
      node ./dist/index.js
      • You should see the output: Hello, TypeScript! Welcome, Student!.