When encountering an unsolvable bug: restart, reinstall, rewrite (the ultimate trio).

Restart: The Most Basic Solution

When encountering a bug, a programmer's first instinct is often to restart. This seemingly simple action has profound underlying principles:

1. State Reset: Browsers generate a large amount of memory state during runtime, and restarting can clear these potential issues.
2. Cache Clearance: Especially in front-end development, browser caches often lead to bizarre behaviors.
3. Environment Refresh: Reload all dependencies and resource files.

// Typical memory leak scenario
function createLeak() {
  const hugeArray = new Array(1000000).fill('*');
  window.addEventListener('resize', () => {
    console.log(hugeArray.length); // Closure maintains reference
  });
}
// Restarting the browser is a quick fix for such memory issues.

Real-world case: An e-commerce website occasionally failed to update the shopping cart. Investigation revealed that the Service Worker cached an old version of the API response. The issue disappeared after restarting the browser.

Reinstall: The Ultimate Solution for Dependency Management

When restarting doesn't work, reinstalling dependencies is often the next step:

The node_modules Black Hole Problem

A familiar scenario for front-end developers:

rm -rf node_modules && npm install

Specific Steps

1. Delete lock files (package-lock.json or yarn.lock).
2. Clear global cache (npm cache clean --force).
3. Reinstall dependencies.

Common Resolved Cases:

• Babel transpilation errors
• Webpack build failures
• Vue/React version conflicts

// Typical version conflict symptom
import { useState } from 'react';
// Error: Hooks can only be called inside function components (actually caused by multiple React versions being installed).

Rewrite: The Ultimate Solution of Starting Over

When conventional methods fail, rewriting the code may be necessary:

Typical Scenarios Requiring Rewrites

1. Legacy code no one understands.
2. Severe design flaws.
3. Outdated technology stacks.

Incremental Rewriting Strategy

// Old code
function oldRender(data) {
  let html = '';
  data.forEach(item => {
    html += `<div>${item.name}</div>`;
  });
  document.getElementById('app').innerHTML = html;
}

// New approach (gradual replacement)
class ModernRenderer {
  constructor(selector) {
    this.container = document.querySelector(selector);
  }
  
  render(data) {
    this.container.innerHTML = data.map(item => `
      <div class="item">${item.name}</div>
    `).join('');
  }
}

Rewrite Decision Matrix

The Supporting Role of Debugging Tools

Before resorting to the "three-step solution," modern debugging tools should be fully utilized:

Advanced Chrome DevTools Techniques

// Conditional breakpoint example
function processItems(items) {
  items.forEach((item, index) => {
    // Right-click the line number to set a condition: index === 5
    console.log(item); 
  });
}

Performance Analysis in Practice

// Using the Performance API for measurement
function measure() {
  performance.mark('start');
  // Execute the code to be tested
  heavyCalculation();
  performance.mark('end');
  
  performance.measure('calc', 'start', 'end');
  console.log(performance.getEntriesByName('calc'));
}

Prevention Over Cure: Best Practices

Reduce the frequency of using the "three-step solution":

1. Comprehensive Testing System

// Example unit test
describe('Shopping Cart Calculation', () => {
  it('should handle discounts correctly', () => {
    const cart = new ShoppingCart();
    cart.add({price: 100, discount: 0.2});
    expect(cart.total).toBe(80);
  });
});

2. Monitoring System Implementation

// Front-end error monitoring example
window.addEventListener('error', (event) => {
  fetch('/log/error', {
    method: 'POST',
    body: JSON.stringify({
      message: event.message,
      stack: event.error.stack,
      url: location.href
    })
  });
});

3. Documentation Culture Cultivation

## Project Setup Guide

### Environment Requirements
- Node 16+
- Latest version of Chrome

### Known Issues
1. Animation lag in Safari: Optimize using `will-change`.
2. IE11 not supported: Load polyfills.