Counter with Even/Odd Indicator - Inferno Typing CST Test

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Counter with Even/Odd Indicator — Inferno Code

Shows whether the current count is even or odd.

import { render, Component } from 'inferno';

class Counter extends Component {
	state = { count: 0, isDark: false };

	increment = () => this.setState({ count: this.state.count + 1 });
	decrement = () => this.setState({ count: this.state.count - 1 });
	reset = () => this.setState({ count: 0 });
	toggleTheme = () => this.setState({ isDark: !this.state.isDark });

	render() {
		return (
		<div className={this.state.isDark ? 'dark-theme' : 'light-theme'}>
		<h2>Counter: {this.state.count} ({this.state.count % 2 === 0 ? 'Even' : 'Odd'})</h2>
		<div>
		<button onClick={this.increment}>+</button>
		<button onClick={this.decrement}>-</button>
		<button onClick={this.reset}>Reset</button>
		</div>
		<button onClick={this.toggleTheme}>Toggle Theme</button>
		</div>
		);
	}
}

render(<Counter />, document.body);

Inferno Language Guide

Inferno.js is an extremely fast, lightweight JavaScript library for building high-performance user interfaces. It uses a React-like API and Virtual DOM but is optimized for speed, small size, and predictable rendering.

Primary Use Cases

▸High-performance SPAs
▸Real-time dashboards and charts
▸Embedded widgets with small footprint
▸React-compatible environments needing speed
▸Apps requiring extremely fast client-side rendering

Notable Features

▸Ultra-fast Virtual DOM (faster than React in many benchmarks)
▸React-like components and lifecycle
▸Small bundle size (~9 KB)
▸Server-side rendering support
▸Partial React API compatibility

Origin & Creator

Created by Dominic Gannaway in 2016 as a high-performance alternative to React, with an emphasis on speed and small bundle size.

Industrial Note

Inferno is primarily used in performance-sensitive environments like financial dashboards, advertising tech, streaming interfaces, and embedded web widgets.

Quick Explain

▸Inferno provides a React-compatible API focused heavily on performance.
▸It uses a highly optimized Virtual DOM engine for minimal overhead.
▸Its architecture makes it suitable for real-time UIs, embedded widgets, and performance-critical apps.

Core Features

▸JSX + components
▸Virtual DOM diffing
▸Lifecycle hooks (componentDidMount, etc.)
▸Functional components supported
▸Efficient event handling system

Learning Path

▸Start with JSX + basic components
▸Understand VDOM diffing
▸Learn state & lifecycle methods
▸Practice high-performance techniques
▸Build SSR apps with `inferno-server`

Practical Examples

▸Simple counter component
▸High-frequency updating dashboard
▸Real-time stock ticker rendering
▸SSR-rendered landing page
▸Embedded widget with tiny bundle size

Comparisons

▸Faster than React - optimized VDOM
▸Smaller than React - tiny bundle
▸Less ecosystem than React/Vue
▸Similar API to React (easy migration)
▸Better suited for high-performance UIs

Strengths

▸One of the fastest UI libraries available
▸Very small and lightweight
▸Easy migration from React
▸Great SSR performance
▸Stable API with minimal overhead

Limitations

▸Smaller ecosystem than React/Vue
▸Some advanced React features not supported
▸Less community activity
▸Fewer tutorials and third-party libraries
▸Maintenance pace slower than big frameworks

When NOT to Use

▸When needing huge ecosystem support
▸When using React-specific hooks/features
▸When building massive enterprise apps
▸When team is unfamiliar with smaller libs
▸When SEO requires full React SSR ecosystem

Cheat Sheet

▸`Inferno.render(vnode, container)` - render app
▸JSX requires babel-plugin-inferno
▸Functional components recommended
▸Use `class extends Component` for stateful components
▸`inferno-create-element` for h() syntax

FAQ

▸Is Inferno faster than React?
▸Yes - its VDOM is extremely optimized.
▸Is Inferno compatible with React?
▸Partially - many React libs work, but not all.
▸Does Inferno support hooks?
▸No - only class and functional components.
▸Does Inferno support SSR?
▸Yes - with `inferno-server`.
▸Is the library still maintained?
▸Yes, but at a slower pace than major frameworks.

30-Day Skill Plan

▸Week 1: Components + JSX
▸Week 2: State mgmt + lifecycle
▸Week 3: Performance tuning
▸Week 4: SSR + hydration
▸Week 5: Embeddable micro-widgets

Final Summary

▸Inferno.js is a blazing-fast, lightweight alternative to React.
▸Its performance-focused Virtual DOM makes it ideal for real-time UIs.
▸React-style API lowers learning curve.
▸Best suited for dashboards, embedded widgets, and performance-heavy UIs.
▸Small ecosystem but extremely powerful in its niche.

Project Structure

▸src/components/ - UI components
▸src/index.js - app entry
▸public/index.html - mount point
▸babel.config.js - JSX transform
▸vite/webpack config - bundlers

Monetization

▸Performance-sensitive dashboards
▸Real-time analytics products
▸Embedded widget development
▸Migration from React to lightweight stacks
▸Optimization consulting

Productivity Tips

▸Use Babel plugin for JSX speed
▸Keep components pure
▸Use functional components
▸Enable production mode
▸Benchmark frequent updates

Basic Concepts

▸JSX + component rendering
▸Functional and class components
▸Props + state system
▸Virtual DOM re-rendering
▸Event handlers and lifecycle hooks

Official Docs

More Inferno Typing Exercises

Inferno Simple Counter Inferno Counter with Step Inferno Counter with Min/Max Inferno Counter with Auto Increment Inferno Counter with Double Increment Inferno Counter with LocalStorage Inferno Counter with Color Themes

Practice Other Languages

C React Python C++Rust TypeScript Kotlin PHP Java C#Ruby Mql Cql N1ql Cypher

Counter with Even/Odd Indicator — Inferno Code

Shows whether the current count is even or odd.

import { render, Component } from 'inferno'; class Counter extends Component { state = { count: 0, isDark: false }; increment = () => this.setState({ count: this.state.count + 1 }); decrement = () => this.setState({ count: this.state.count - 1 }); reset = () => this.setState({ count: 0 }); toggleTheme = () => this.setState({ isDark: !this.state.isDark }); render() { return ( <div className={this.state.isDark ? 'dark-theme' : 'light-theme'}> <h2>Counter: {this.state.count} ({this.state.count % 2 === 0 ? 'Even' : 'Odd'})</h2> <div> <button onClick={this.increment}>+</button> <button onClick={this.decrement}>-</button> <button onClick={this.reset}>Reset</button> </div> <button onClick={this.toggleTheme}>Toggle Theme</button> </div> ); } } render(<Counter />, document.body);

Inferno Language Guide

Primary Use Cases

▸High-performance SPAs
▸Real-time dashboards and charts
▸Embedded widgets with small footprint
▸React-compatible environments needing speed
▸Apps requiring extremely fast client-side rendering

Notable Features

▸Ultra-fast Virtual DOM (faster than React in many benchmarks)
▸React-like components and lifecycle
▸Small bundle size (~9 KB)
▸Server-side rendering support
▸Partial React API compatibility

Origin & Creator

Created by Dominic Gannaway in 2016 as a high-performance alternative to React, with an emphasis on speed and small bundle size.

Industrial Note

Inferno is primarily used in performance-sensitive environments like financial dashboards, advertising tech, streaming interfaces, and embedded web widgets.