tryCatch Function

This function provides a structured way to handle asynchronous operations that may either succeed or fail, returning a Result type that encapsulates the outcome.

Function Signature

export async function tryCatch<T, E = Error>(
  promise: Promise<T>,
): Promise<Result<T, E>>

Description

The tryCatch function takes a Promise<T> as input and attempts to resolve it. If the promise resolves successfully, it returns a Success<T> object containing the resolved value and null for the error. If the promise rejects, it catches the error and returns a Failure<E> object containing null for the response and the caught error.

Result Type

The function returns a Result<T, E> type, which is a discriminated union of Success<T> and Failure<E>.

type Success<T> = {
  response: T;
  error: null;
};

type Failure<E> = {
  response: null;
  error: E;
};

type Result<T, E = Error> = Success<T> | Failure<E>;

• Success<T>: Represents a successful operation, where T is the type of the resolved value.
• Failure<E>: Represents a failed operation, where E is the type of the error. The default error type is Error.

Usage

async function main() {
  const getPost = fetch('https://jsonplaceholder.typicode.com/todos/1')
  
  // const result = await tryCatch(getPost); or
  const {response, error} = await tryCatch(getPost);
  if(error !== null) return error;
  
  const data = await response.json()
  console.log(data)
}

main();

Benefits

• Provides a consistent and type-safe way to handle asynchronous results.
• Eliminates the need for repetitive try...catch blocks.
• Makes it easier to handle errors in a structured manner.
• Allows the type of the error to be specified.