state-management

import { create } from 'zustand'
import { persist } from 'zustand/middleware'

interface FilterState {
  search: string
  category: string | null

import SwiftUI

struct ContentView: View {
    @State private var username = ""
    @State private var isLoggedIn = false
    @StateObject private var viewModel = LoginViewModel()

/* Interactive pseudo-classes */
a:link { color: blue; }
a:visited { color: purple; }
a:hover { text-decoration: underline; }
a:active { color: red; }
a:focus { outline: 2px solid orange; }

import React, { createContext, useContext, useState, useEffect, ReactNode } from 'react'
import { User } from '@/types'
import api from '@/services/api'

interface AuthContextType {
  user: User | null

<nav id="main-navbar"
     data-turbo-permanent
     data-controller="navbar"
     data-navbar-menu-open-value="false"
     class="navbar">
  <div class="navbar-inner">

export class QueryCache {
  constructor() {
    this.entries = new Map();
  }

  getEntry(key) {

import { useReducer } from 'react'

interface FormState {
  values: Record<string, any>
  errors: Record<string, string>
  touched: Record<string, boolean>

export interface Post {
  id: string;
  title: string;
  updatedAt: string;
}

export type Validator = (value: string) => string | null;

export const required = (message = 'This field is required'): Validator => {
  return (value) => (value.trim().length === 0 ? message : null);
};

import { useEffect, useState } from "react";

export function useDebouncedValue<T>(value: T, delay = 800): T {
  const [debounced, setDebounced] = useState<T>(value);

  useEffect(() => {

class OnboardingForm
  include ActiveModel::Model
  include ActiveModel::Attributes

  STEPS = %i[account profile preferences].freeze

package optimistic

import (
	"errors"
	"sync"
)