Try TS

A Opt-in TypeScript Result type implementation for elegant error handling with full type safety.

Installation

Features

• Opt-in Type-safe error handling
• Full TypeScript support
• Zero dependencies

Usage

Basic Usage

import { ResultError, withResult } from 'try-ts';

// Define a custom error type
type UserError = "USER_NOT_FOUND";

// Wrap the async function with `withResult` to enable type-safe error handling
const getUser = withResult<UserError>()(async (id: string) => {
  // Fetch user data
  const response = await fetch(`https://jsonplaceholder.typicode.com/users/${id}`);
  const data = await response.json() as { id: string; name: string };

  // Check for 404 error and return a ResultError with custom error code
  if (response.status === 404) {
    return new ResultError("USER_NOT_FOUND", `User with id ${id} not found`); // `ResultError<UserError>`
  }

  return data;
});

async function main() {
  // Fetch user info; `user` is of type `{ id: string; name: string }` 
  const user = await getUser("not-found"); 
  console.log(user.name); 

  // `userResult` is of type `Result<{ id: string; name: string }, ResultError<UserError>>`
  const userResult = await getUser("not-found").try(); 

  // Check if the operation was successful and handle accordingly
  if (userResult.isOk) {
    // `userResult.value` is `{ id: string; name: string }`
    console.log("User found:", userResult.value); 
  } else {
    // Handle different error cases based on error code
    switch (userResult.error.code) {
      case "USER_NOT_FOUND": 
        console.error("User not found...");
        break;
      default:
        console.error("An unexpected error occurred");
        break;
    }
  }
}

main();