Typia Guide Documents

Transformer

Guide Documents · Playground (Online IDE) · Github Repository

typia is a transformer library converting TypeScript types to runtime function.

If you call one of the typia function, it would be compiled like below. This is the key concept of typia, transforming TypeScript type to a runtime function. The typia.is<T>() function is transformed to a dedicated type checker by analyzing the target type T in the compilation level.

This feature enables developers to ensure type safety in their applications, leveraging TypeScript’s static typing while also providing runtime validation. Instead of defining additional schemas, you can simply utilize the pure TypeScript type itself.

//----
// examples/checkString.ts
//----
import typia, { tags } from "typia";
export const checkString = typia.createIs<string>();
 
//----
// examples/checkUUID.js
//----
import typia from "typia";
export const checkString = (() => {
  return (input) => "string" === typeof input;
})();

Key Features

Super-fast Runtime Validator

typia.assert<T>(input)

20,000x faster than class-validator.

Stable than any others, and only one supporting complicate union type.

In the backend server side, it boosts up performance about 10x up.

Fast JSON Serialization

typia.json.stringify<T>(input)

200x faster than class-transformer.

Also supports type safe JSON parser, and JSON schema generator.

In the backend server side, it boosts up performance about 10x up.

LLM Function Calling App

typia.llm.application<App>()

LLM Function Calling Application Composer

Creates LLM function call schemas from a native TypeScript class or interface type.

LLM will select proper function to call and fill arguments in the conversations with human.

Easy Protocol Buffer

typia.protobuf.encode<T>(input)

Full spec of protobuf.

Only one supporting full spec of protobuf in the TypeScript ecosystem.

No need extra *.proto schema file. Just fine with native TypeScript type.

Random Data Generator

typia.random<T>()

Universal random generator.

The best mock-up data generator with native TypeScript type.

In the backend side, it boosts up productivity dramatically.