🚀 JavaScript Code Editor — Built from Scratch

A modern JavaScript code editor playground with real-time code analysis, developer insights, and a non-intrusive floating insights sidebar.

A pure vanilla JavaScript code editor with advanced developer insights, real-time analysis, and professional-grade features. Built without any external dependencies, or third-party packages - just clean, efficient code.

✨ Key Features

🎯 Pure Vanilla JavaScript

• Zero Dependencies: No external libraries, frameworks, or packages
• No AI Integration: Human-crafted code with intelligent analysis
• Lightweight: Fast loading and execution
• Modern ES6+: Clean, readable JavaScript using latest standards

🔧 Advanced Code Editor

• Real-time Syntax Highlighting: Dynamic JavaScript syntax highlighting
• Line Numbers: Professional line numbering with scroll synchronization
• Smart Indentation: Automatic code formatting and indentation
• Multi-theme Support: Light and dark themes with smooth transitions
• Responsive Design: Works perfectly on desktop and mobile devices

📊 DevInsights Panel - Advanced Code Analysis

Our crown jewel - a comprehensive developer insights panel that provides:

Real-Time Memory & Execution Tracker

• Dynamic Step-by-Step Execution Flow: Professional stepper UI showing each execution phase
• Memory Usage Analysis: Peak memory tracking with DOM operations and network requests
• Garbage Collection Monitoring: Real-time GC cycle tracking and memory cleanup analysis
• Performance Metrics: Actual execution timing (not estimates) with millisecond precision

Comprehensive Code Pattern Detection

• Functional Programming: Detects map, filter, reduce, forEach, find, some, every
• Async Patterns: async/await, Promises, fetch, axios, legacy XMLHttpRequest
• Loop Analysis: All loop types (for, while, do-while, for-in, for-of)
• Design Patterns: Classes, factory, observer, module, singleton patterns
• Error Handling: try/catch blocks, error throwing, cleanup operations
• Memory Leak Detection: Unreleased intervals, event listeners, unclosed resources

Professional UI Components

• Numbered Stepper: Clean, professional execution flow with connecting lines
• Status-Based Colors: Green/yellow/red indicators for performance warnings
• Code Quality Scoring: 0-100 performance scores with actionable recommendations
• Complexity Analysis: Big O notation analysis and optimization suggestions
• Smart Summary Bar: Real-time code metrics display with comprehensive hover tooltips
• Detailed Hover Analysis: Intelligent tooltips showing only non-zero values for:
  • Function Breakdown: Regular, arrow, async, methods, constructors, generators, higher-order
  • Loop Analysis: For, while, do-while, for-in, for-of, forEach, functional methods
  • Async Operations: Async functions, await expressions, promises, fetch calls, timers, callbacks
  • Performance Rating: Dynamic performance assessment with execution metrics

🎨 Professional Design

• Modern UI: Clean, minimalist design with professional typography
• Theme System: Comprehensive light/dark mode with CSS variables
• Responsive Layout: Mobile-first design that works on all screen sizes
• Smooth Animations: Subtle transitions and fade-in effects
• Enterprise-Grade Styling: Professional color schemes and spacing

🛠️ Technical Architecture

Core Technologies

• HTML5: Semantic markup with modern standards
• CSS3: Advanced styling with Grid, Flexbox, and CSS Variables
• Vanilla JavaScript: Pure ES6+ with no external dependencies
• DOM APIs: Direct manipulation for optimal performance

🚀 Getting Started

1. Clone or Download the repository
2. Open index.html in any modern web browser
3. Start Coding - No installation, setup, or dependencies required!

💡 Example Code to Test

Functional Programming Example

const numbers = [1, 2, 3, 4, 5, 1, 2, 3, 4, 5];
const result = numbers
  .filter(n => n % 2 === 0)    
  .map(n => n * 2)             
  .reduce((sum, n) => sum + n, 0); 

console.log({result})

function createUserArray(count) {
  return Array.from({ length: count }, (_, i) => ({
    id: i + 1,
    name: `User ${i + 1}`,
    role: i % 2 === 0 ? "Admin" : "Editor"
  }));
}

const users = createUserArray(10);
console.log(users);

Async Operations Example

async function fetchUserData() {
    const response = await fetch('https://jsonplaceholder.typicode.com/todos/2');
    const data = await response.json();
    
    //document.getElementById('output').innerHTML = data.title;
    console.log('User loaded:', data);
    
    return data;
}

fetchUserData();

function heavySyncTask() {
  for (let i = 0; i < 1e6; i++) {}
}
async function fetchData() {
  await new Promise((r) => setTimeout(r, 100));
  console.log("Data received!");
}
console.log("Start");
heavySyncTask();
fetchData();
console.log("End");

Complex Analysis Example

async function sequentialCalls() {
    console.time("Sequential");
    const todo1 = await fetch("https://jsonplaceholder.typicode.com/todos/1").then((r) => r.json());
    const todo2 = await fetch("https://jsonplaceholder.typicode.com/todos/2").then((r) => r.json());
    console.log("Todo 1:", todo1);
    console.log("Todo 2:", todo2);
    console.timeEnd("Sequential");
}

async function parallelCalls() {
    console.time("Parallel");
    const [todo1, todo2] = await Promise.all([
        fetch("https://jsonplaceholder.typicode.com/todos/1").then((r) => r.json()),
        fetch("https://jsonplaceholder.typicode.com/todos/2").then((r) => r.json()),
    ]);
    console.log("Todo 1:", todo1);
    console.log("Todo 2:", todo2);
    console.timeEnd("Parallel");
}


sequentialCalls();
parallelCalls();

🎯 DevInsights Panel Features

What You'll See:

• Code Overview: Quality scores and complexity metrics
• Complexity Analysis: Big O notation with performance ratings
• Performance Metrics: Real-time execution analysis
• Code Quality: Best practices and optimization suggestions
• Deep Analysis: Unified memory and execution tracker with:
  • Memory usage (Peak Memory, DOM Ops, Network, Errors, GC)
  • Professional stepper showing execution flow
  • Step-by-step breakdown with memory allocation details
  • Advanced code analysis grid with pattern detection

Real-Time Insights:

• Memory Tracking: See actual memory usage and allocation
• Execution Timing: Precise millisecond timing for each operation
• Pattern Recognition: Automatic detection of coding patterns and best practices
• Performance Warnings: Color-coded alerts for potential issues
• Optimization Tips: Actionable recommendations for code improvement

🌟 Why This Editor?

For Developers:

• Learning Tool: Perfect for understanding JavaScript execution and performance
• Code Analysis: Deep insights into your code's behavior and efficiency
• No Setup: Works immediately without any installation or configuration
• Professional Grade: Enterprise-level features in a simple package

For Educators:

• Teaching Aid: Visual representation of code execution and memory usage
• Pattern Recognition: Helps students understand different programming patterns
• Performance Education: Real-time feedback on code efficiency

For Professionals:

• Quick Prototyping: Fast code testing and analysis
• Performance Debugging: Identify bottlenecks and optimization opportunities
• Code Review: Comprehensive analysis for code quality assessment

🔧 Browser Compatibility

• ✅ Chrome/Chromium (Recommended)
• ✅ Firefox
• ✅ Safari
• ✅ Edge

📝 License

Open source - feel free to use, modify, and distribute!

🤝 Contributing

This is a pure vanilla JavaScript project. Contributions welcome! Please maintain the no-dependency philosophy.

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Built with ❤️ using pure vanilla JavaScript - No AI, No packages, No dependencies!`