TypeScript Academy · Lesson

Typed Error Classes and Hierarchies

Create custom error classes with discriminated types.

Welcome

Custom error classes in TypeScript give errors a type hierarchy for safe, structured handling.

Create a base AppError class with a statusCode.

class AppError extends Error {
  constructor(public message: string, public statusCode = 500) {
    super(message);
    this.name = 'AppError';
  }
}