Tasks

Task 1: Basic Data Types and First Program

Objective: Write a TypeScript program that outputs a welcome message.

Instructions:

• Create a TypeScript program.
• Print the following message to the console:

  Hello World, I will complete this course successfully and become a Next level Web Developer!

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Task 2: Functions, Optional, and Literal Types

Objective: Create a function with parameters and an optional literal type.

Instructions:

• Define a function that takes:
  • name (string)
  • age (number)
  • role (optional, with type 'admin' | 'user' | 'guest')
• The function should log these values or perform a basic action.

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Task 3: Object Types, Type Alias, & Literal Types

Objective: Define a structured Person object using Type Aliases.

Instructions:

• Define a Person type alias with properties for Name, Address, Hair and Eye Color, Income and Expense, Hobbies, Family Members, Job, Skills, Marital Status, and Friends.

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Task 4: Union and Intersection Types

Objective: Create union and intersection types using interfaces.

Instructions:

• Define interfaces Book and Magazine.
• Create:
  • A type that is a union of Book and Magazine.
  • A type that is an intersection of Book and Magazine.

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Task 5: Function Type

Objective: Write a function that reverses a string.

Instructions:

• Write a function reverseString that:
  • Takes a single string argument.
  • Returns the string in reverse order.
  • Example:
    • Input: "hello"
    • Output: "olleh"

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Task 6: Spread and Rest Operators, Destructuring

Objective: Write a function that uses the rest operator for variable-length arguments.

Instructions:

• Create a function that takes multiple numeric arguments (using the rest operator) and returns the sum of all arguments.

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Task 7: Type Assertion and Narrowing

Objective: Write a function that behaves differently based on the input type.

Instructions:

• Create a function that accepts a parameter of type string | number.
• The function should:
  • Return the length if the input is a string.
  • Return the square if the input is a number.

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Task 8: Intersection Types

Objective: Practice using intersection types.

Instructions:

• Create a type AdminUser that is an intersection of:
  • User with properties name and email
  • Admin with property adminLevel
• Write a function describeAdmin(user: AdminUser): string that returns a description of the admin user.

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Task 9: Optional Chaining

Objective: Use optional chaining with nested objects.

Instructions:

• Write a function getEmployeeCity(employee) that safely retrieves the city of an employee from a nested object using optional chaining.

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Task 10: Nullish Coalescing

Objective: Handle null and undefined values using nullish coalescing.

Instructions:

• Write a function getDisplayName(name: string | null | undefined): string that returns "Anonymous" if name is null or undefined.

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Task 11: Unknown Type

Objective: Handle different types with the unknown type.

Instructions:

• Write a function processData(data: unknown) that:
  • Checks if data is a string and returns the uppercased version.
  • If data is a number, returns the square of it.

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Task 12: Never Type

Objective: Use the never type for functions that don’t return.

Instructions:

• Write a function handleError that:
  • Accepts a message: string.
  • Throws an error with the given message.
  • Use the never return type to indicate that this function never returns.

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Task 13: Generics with Functions and Interfaces

Objective: Use generics to handle different types.

Instructions:

• Create a generic function that:
  • Accepts an array of any type.
  • Returns a new array with duplicate values removed.

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Task 14: Asynchronous TypeScript and Type Aliases

Objective: Simulate an asynchronous operation with TypeScript.

Instructions:

• Write an asynchronous function that:
  • Simulates fetching user data (containing name and age).
  • Returns the data after a short delay.

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Task 15: Type Guards

Objective: Create custom type guards for more accurate type checking.

Instructions:

• Write a function isString(value: unknown): value is string that checks if a value is a string.
• Use this in another function printUpperCase(value: unknown): void that prints the value in uppercase if it’s a string.

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Task 16: Utility Types and Keyof Constraints

Objective: Access object properties dynamically using keyof.

Instructions:

• Create a function that:
  • Takes an object and a key.
  • Returns the property value from the object based on the provided key.
  • Use keyof to constrain the key to valid properties of the object.

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Happy coding!