TypeScript Masterclass 2025 Edition - React + NodeJS Project

Understand why BigInt was introduced to handle numbers beyond the maximum safe integer in JavaScript, and how to declare BigInt using the constructor or a numeric literal ending in n.

Examine how any type acts as the default JavaScript behavior and why you should use stricter types. Understand implicit any and the tsconfig noImplicitAny option for type safety.

Understand the TypeScript type hierarchy, where moving down yields stricter types and moving up yields more liberal types, with examples like any, string, unknown, and never shaping subtyping. Explore how array, object, and tuple relate, learn to prefer the most specific type, and reference the never type and diagram in future lessons.

discover how to strictly type objects in TypeScript by defining a type alias for a post with title, content, and date, and reuse it to avoid repeating object annotations.

Explore strictly typing nested objects in TypeScript by defining an author with name, age, and email, and reuse it via a dedicated author type alias.

Use index signatures to strictly type dynamic object properties in TypeScript, modeling an awards object as string keys mapping to award details with name and date.

Explore how TypeScript unions for objects combine dog and cat types, requiring a value to include all properties of at least one side (name, barks or purrs), with optional extras.

Learn how discriminating unions in TypeScript use a common literal state to distinguish loading, failed, and success network states, enabling safe access to code or response data.

Discover how enums compile to JavaScript and become runtime objects you can use in code, unlike type definitions, with examples like direction and roles transformed into objects.

Master TypeScript basics by building typed arrays, string arrays, and a read-only array and tuple, then create a status enum and an object that emulates an enum.

Declare strictly typed functions in TypeScript by typing parameters name and age and returning a string, using function declarations, function expressions, and arrow functions with template literals and unions.

Apply type aliases to strictly annotate parameter and return types in a TypeScript example, converting a person’s age from years to months using a year or month age unit.

Explore void and never types in TypeScript by strictly typing functions that don’t return, and compare when to use void versus never, including their relationship and practical examples.

Explore rest parameters in TypeScript to type unlimited function arguments, using the rest operator to handle a number array, map results, and enforce fixed-length tuples for two-argument functions.

Learn parameter destructuring in TypeScript by extracting a, b, and c from a numbers object, infer their types, and enforce strict typing with type errors when values don't match.

Explore function overloading in TypeScript by defining multiple call signatures for a reservation function, using an object-like overload structure, and leveraging union and never types to handle multiple argument scenarios.

Develop a practical, polymorphic filter in TypeScript using generics and a predicate. Validate it with numbers and animals, returning only items that meet the condition.

Discover how TypeScript classes serve as blueprints to create object instances with shared properties and methods, such as name, email, and a greet method.

Use the this keyword to assign constructor parameters to class fields and access them with dot notation in TypeScript. Understand initialization checks and dynamic, per-instance properties.

See how TypeScript treats classes as blueprints that define object types, enforcing properties and methods in each instance. Learn to use classes as types with strict typing and type inference.

Learn how inheritance works in TypeScript by extending a user class to create admin, which inherits user properties and adds an is admin property via the extends keyword.

Explore how to implement constructors in a derived admin class, invoke the parent constructor with super, and manage dynamic properties like name, email, last name, and users reporting in TypeScript.

Practice class concepts with a hands-on exercise, using the better comments VSCode extension to read highlighted JavaScript comments. Find the exercise link in the resources section and try it yourself.

Explore protected properties in TypeScript, where access stays within the parent and child classes but does not appear on the final object, unlike public properties.

Understand how private properties restrict access to the parent class only, not the child or final objects, via a user class example.

Override methods in child classes in TypeScript by redefining greet with the same signature to produce different string outputs for user and admin instances.

Learn how to enforce age validation in the TypeScript class constructor and use accessors and mutators to expose full name as a property.

Master TypeScript classes by building an employee and a manager, using public, private, protected properties, constructor shorthand, salary getters/setters, a static company name, and a getDetails override with department.

Explore abstract classes and interfaces in TypeScript, starting with static members and inheritance, then mastering abstract methods and constructor properties inside abstract classes, followed by interfaces, generics, and access modifiers.

Demonstrate how a protected constructor in the abstract department class restricts instantiation to child classes like IT and admin departments. See how super calls assign names and prevent misnamed instances.

Explore how three generics power a flexible automobile interface by passing enums or primitive types for type, brand, and colors, illustrated with Ferrari, Honda, and Toyota examples.

Apply TypeScript to implement multiple interfaces in a truck class, adding a commercial vehicle interface with capacity and license renewal date, and build modular code shared across classes.

TypeScript lets a class inherit from a single parent class but can implement multiple interfaces, solving the multiple inheritance issue and enabling more flexible designs.

Explore the differences between abstract classes and interfaces in TypeScript, including binding contracts, implementations, and how each defines properties like name, email, and phone.

Compare interfaces and abstract classes in TypeScript by showing how interfaces declare greetings as call signatures without implementations, while abstract classes provide concrete methods and static methods.

Explore how the TypeScript compiler converts ts files like index.ts to js, loads them via index.html, and uses a tsconfig-based root directory with watch script to generate app.js and more.

Explore how the tsconfig exclude and include options control what TypeScript compiles, including handling of node_modules and wildcard patterns. Learn practical examples to finely tune your project's compilation scope.

Explore how the tsconfig target sets the JavaScript output version for TypeScript, factors affecting choice like browser, React, or Node environments, and how boilerplates reference ES5 with development resources.

Enable source maps in tsconfig to debug TypeScript directly in the browser, view app.ts instead of app.js, and set breakpoints with the Chrome debugger using app.js.map.