TypeScript Basic Types and Generics Exercises

This document contains exercises to help you practice working with basic types and generics in TypeScript.

Basic Types

These exercises focus on using basic types like number, string, boolean, null, undefined, unknown, any, tuples, enums, and type unions.

Tasks:

1. Convert JavaScript code to TypeScript: Convert the provided JavaScript code to TypeScript, specifying appropriate types for all variables.
2. Assign a type to a variable of any type: Define a variable that can store values of any type.
3. Access unknown type safely: Assign an unknown type variable to another variable of a known type safely.
4. Create a tuple with specific types: Define a tuple that ensures the first element is a string and the second element is a number.
5. Define variables with union and literal types:
   • Create a variable that can accept a string or a number.
   • Create a variable that can only accept one of two specific string values.
6. Specify types for function arguments and return values: Add type information to function arguments and return values for clarity and safety.
7. Create a function based on a day of the week enum: Define a function that takes a day of the week from your enum and returns whether it's a weekday or weekend.
8. Create a union type for gender: Define a union type that can represent "male" or "female" gender values.
9. Create a type for similar objects: Create a new type that can represent two provided objects with similar properties and structures.

Generics

These exercises guide you through using generics in functions, interfaces, classes, and utilities like Pick and Record.

Tasks:

1. Create a function with a generic return type: Define a function that returns a promise with a specified generic type.
2. Compare objects with generics and Pick: Use generics and Pick to compare two objects with fields of the specified generic type.
3. Merge objects using generics: Create a generic function that merges two objects of any type.
4. Fix type errors in classes with generics and interfaces: Use generics and interfaces to address type errors in provided classes.
5. Implement a KeyValuePair interface with generics: Define an interface KeyValuePair that uses generics to accept any key and value types.
6. Fix form update function type: Correct the type of a function argument to allow partial updates of a user object.
7. Create a role description object using Record: Implement a RoleDescription object using Record to map user roles to their descriptions.
8. Exclude specific fields from a type with generics: Create a new type that excludes a specific field ("errors") from an existing type.