How do branded types improve my code?

Branded types allow you to distinguish between identical primitive types (like a UserId string vs. a PostId string) at the type level, preventing you from accidentally passing the wrong ID to a function.

What is exhaustive matching in TypeScript?

Exhaustive matching is a technique, often implemented with libraries like ts-pattern, that ensures every possible variant of a discriminated union is handled by the code. If a new type is added, the compiler will flag any missing logic.

Does this skill work with standard TypeScript?

Yes, while it recommends the 'ts-pattern' library for advanced matching, the core patterns for immutable data, discriminated unions, and Result types are all based on standard TypeScript best practices.

Why should I use Result types instead of try-catch?

Result types force you to handle potential errors explicitly at compile-time as part of the data flow, making your code more predictable and preventing unhandled runtime exceptions common with try-catch blocks.

TypeScript Type Safety Patterns

Name: TypeScript Type Safety Patterns
Author: Higashi-Kota

byHigashi-Kota

0•

開発者ツール

Implements robust, type-safe architectural patterns using discriminated unions, Result types, and exhaustive pattern matching to eliminate runtime exceptions.

This skill provides a comprehensive reference and implementation guide for developers looking to write safer, more predictable TypeScript code. By leveraging functional programming concepts like Result and Option types, along with the ts-pattern library for exhaustive matching, it helps teams move away from error-prone practices such as type assertions and unhandled exceptions. It includes patterns for immutable data structures, branded types to prevent ID confusion, and readonly collections, ensuring your core business logic remains pure, robust, and easy to reason about during development.

主な機能

01Branded types (nominal typing) to ensure compile-time distinction between primitive values

02Discriminated union templates for clean and extensible domain modeling

03Immutable class and readonly collection patterns for predictable state management

04Exhaustive pattern matching integration using ts-pattern for complete branch coverage

05Implementation of Result and Option types for explicit functional error handling

060 GitHub stars

ユースケース

01Refactoring legacy TypeScript codebases to eliminate 'any' types and unsafe assertions

02Building mission-critical business logic that requires high reliability and zero runtime exceptions

03Designing complex domain models where state transitions must be explicitly and safely handled

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add higashi-kota/video-parapara type-patterns

For use in Claude.ai and ChatGPT

Download Skill