Type alias for functions in Typescript - Mini Project: Build & Apply

Type Alias for Functions in TypeScript

📖 Scenario: You are building a simple calculator app. You want to organize your code by giving a name to the type of functions that take two numbers and return a number.

🎯 Goal: Create a type alias called Operation for functions that take two number arguments and return a number. Then use this alias to define functions for addition and multiplication.

📋 What You'll Learn

Create a type alias named Operation for functions with two number parameters returning a number.

Create a function add using the Operation type that returns the sum of two numbers.

Create a function multiply using the Operation type that returns the product of two numbers.

Print the results of add(5, 3) and multiply(5, 3).

💡 Why This Matters

🌍 Real World

Type aliases for functions help keep code organized and clear, especially in apps with many similar functions like calculators or data processors.

💼 Career

Understanding type aliases for functions is important for writing clean, maintainable TypeScript code in professional software development.

1

Create the type alias for functions

Create a type alias called Operation for functions that take two number arguments and return a number.

Typescript

// Your code here

Need a hint?

Use the type keyword followed by the alias name and the function signature.

2

Create the addition function using the type alias

Create a function called add with the type Operation that returns the sum of its two parameters a and b.

Typescript

type Operation = (a: number, b: number) => number;
// Your code here

Need a hint?

Use const add: Operation = (a, b) => a + b; to define the function.

3

Create the multiplication function using the type alias

Create a function called multiply with the type Operation that returns the product of its two parameters a and b.

Typescript

type Operation = (a: number, b: number) => number;

const add: Operation = (a, b) => a + b;
// Your code here

Need a hint?

Define multiply similarly to add, but multiply the two numbers.

4

Print the results of the functions

Print the results of add(5, 3) and multiply(5, 3) using console.log.

Typescript

type Operation = (a: number, b: number) => number;

const add: Operation = (a, b) => a + b;

const multiply: Operation = (a, b) => a * b;
// Your code here

Need a hint?

Use console.log(add(5, 3)); and console.log(multiply(5, 3)); to show the results.