template-literal-types

Model and validate string patterns at compile time with TypeScript template literal types.

Updated Jul 17, 2017

Search Tags:#typescript #dsl #type-level #mapped-types #template-literals #string-patterns

Ready to run

npx skills add https://github.com/luyi985/lyi-bash --skill template-literal-types

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: template-literal-types
Source: https://github.com/luyi985/lyi-bash/tree/main/ai/skills/template-literal-types
Command: npx skills add https://github.com/luyi985/lyi-bash --skill template-literal-types

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Type-safe modeling of strings and DSL parsing using TypeScript template literal types to ensure correct string shapes and transformations at compile time.

Core Features & Use Cases

Model structured string patterns (IDs, paths, URLs) with type-level templates.
Parse and validate DSL-like strings using conditional types and infer.
Transform and map string shapes with mapped types for safer APIs.

Quick Start

Define a template literal type that matches a pattern, such as data-${string}, and use it to constrain related types.

Frequently Asked Questions about template-literal-types

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I validate string patterns at compile time in TypeScript?▼

TypeScript template literal types validate string patterns at compile time by defining constraints like `data-${string}`. This enforces correct string shapes and transformations before runtime, ensuring safer APIs and DSL parsing without adding runtime overhead.

What's the best way to parse DSL strings using TypeScript types?▼

Parsing DSL strings with TypeScript involves using template literal types alongside conditional types and the `infer` keyword. This combination extracts and transforms specific string segments at compile time, enabling type-safe DSL validation directly within your frontend or library codebase.

Does TypeScript support type-level string transformations for API design?▼

TypeScript supports type-level string transformations for API design through template literal types and mapped types. You can model structured string patterns such as URLs and paths, constraining related types to ensure string transformations remain type-safe during development.

Can I use mapped types to transform string shapes in TypeScript?▼

Mapped types transform string shapes in TypeScript by applying template literal types to existing structures. This allows you to parse, validate, and remap string patterns at compile time, resulting in safer APIs and more robust string handling in library code.

Do I need a specific TypeScript version to use template literal types?▼

Template literal types require TypeScript version 4.1 or higher. This version introduced the ability to model string patterns, use conditional types, and apply the `infer` keyword to parse and transform strings at the type level.

Why use compile-time string validation instead of runtime checks for string patterns?▼

Compile-time string validation with template literal types catches pattern mismatches during development rather than at runtime. By modeling structured strings like IDs and paths type-level, you eliminate runtime validation overhead and enforce stricter API safety.