psawn

import { ResultAsync } from 'neverthrow';

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

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

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

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

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import { useState, Activity } from "react";

export default function App() {
  const [show, setShow] = useState(true);

  return (
    <>
      <button onClick={() => setShow(prev => !prev)}>
        Toggle
      </button>

psawn

// Case 1
type ButtonConfig = {
  variant: 'primary' | 'secondary';
  size: 'small' | 'default';
};

const button1: ButtonConfig = {
  variant: 'primary',
  size: 'small',
};

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type User = {
  name: 'psawn';
};

interface LoadingState {
  status: 'loading';
}

interface SuccessState {
  status: 'success';

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const req = {
  method: 'GET',
  url: 'api',
} as const; 
// ^ "as const" converts fields from 'string' to literal types (e.g., exactly 'GET').
// It also makes the object read-only, preventing changes.

function makeReq(url: string, method: 'GET' | 'POST') {
  return '';
}

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// -----------------------------
// 1. Custom sleep using Promise
// -----------------------------
async function testCustomSleep() {
  const sleep = (ms) => new Promise((resolve) => setTimeout(resolve, ms));

  console.log("Sleeping (custom Promise)...");
  await sleep(1000);
  console.log("Done (custom Promise)!");
}