Evaluate JavaScript code directly from command line
📦 Node.js-> Command Line
✨ The Prompt Phrase
node -e "console.log('Hello')"
💻 Code Preview
📦 All-in-One Code
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Evaluate JavaScript code directly from command line - Interactive Tutorial</title>
<link href="https://fonts.googleapis.com/css2?family=Poppins:wght@300;400;600;700;900&family=Fira+Code:wght@400;500;600&display=swap" rel="stylesheet">
<style>
:root {
--bg-primary: #0a0e27;
--bg-secondary: #151932;
--bg-card: #1e2139;
--accent-purple: #a855f7;
--accent-blue: #3b82f6;
--accent-green: #10b981;
--accent-red: #ef4444;
--accent-yellow: #f59e0b;
--accent-pink: #ec4899;
--accent-cyan: #06b6d4;
--accent-lime: #84cc16;
--accent-node: #68a063;
--text-primary: #f8fafc;
--text-secondary: #94a3b8;
--gradient-eval: linear-gradient(135deg, #a855f7 0%, #06b6d4 100%);
--gradient-node: linear-gradient(135deg, #68a063 0%, #84cc16 100%);
--shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}
* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
body {
font-family: 'Poppins', sans-serif;
background: var(--bg-primary);
color: var(--text-primary);
line-height: 1.6;
overflow-x: hidden;
}
.container {
max-width: 1200px;
margin: 0 auto;
padding: 20px;
}
.progress-container {
position: fixed;
top: 0;
left: 0;
width: 100%;
height: 5px;
background: var(--bg-secondary);
z-index: 1000;
}
.progress-bar {
height: 100%;
background: var(--gradient-eval);
width: 0%;
transition: width 0.3s ease;
}
.hero {
text-align: center;
padding: 100px 20px;
background: var(--gradient-eval);
position: relative;
overflow: hidden;
border-radius: 0 0 50px 50px;
}
.hero::before {
content: '';
position: absolute;
top: 0;
left: 0;
right: 0;
bottom: 0;
background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><circle cx="50" cy="50" r="2" fill="white" opacity="0.1"/></svg>');
animation: float 20s linear infinite;
}
@keyframes float {
from { transform: translateY(0); }
to { transform: translateY(-100px); }
}
.hero-content {
position: relative;
z-index: 1;
}
.eval-icon {
font-size: 5rem;
margin-bottom: 20px;
animation: evalBounce 2s ease-in-out infinite;
}
@keyframes evalBounce {
0%, 100% { transform: translateY(0); }
50% { transform: translateY(-20px); }
}
.command-display {
display: inline-block;
background: rgba(0, 0, 0, 0.4);
padding: 25px 40px;
border-radius: 15px;
font-family: 'Fira Code', monospace;
font-size: 1.3rem;
margin: 30px 0;
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animation: pulse 2s ease-in-out infinite;
color: white;
font-weight: 600;
}
@keyframes pulse {
0%, 100% { transform: scale(1); }
50% { transform: scale(1.05); }
}
.hero h1 {
font-size: 3.5rem;
font-weight: 900;
margin-bottom: 20px;
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.hero p {
font-size: 1.4rem;
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}
.section {
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}
.section-title {
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.terminal-dots {
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gap: 6px;
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.terminal-dot {
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.dot-yellow { background: #ffbd2e; }
.dot-green { background: #27c93f; }
.copy-btn {
background: var(--accent-purple);
color: white;
border: none;
padding: 8px 16px;
border-radius: 8px;
cursor: pointer;
font-size: 0.9rem;
transition: all 0.3s ease;
}
.copy-btn:hover {
background: var(--accent-blue);
transform: scale(1.05);
}
.copy-btn.copied {
background: var(--accent-green);
}
pre {
margin: 0;
overflow-x: auto;
}
code {
color: #e0e0e0;
font-size: 0.95rem;
line-height: 1.8;
}
.code-comment { color: #6a9955; }
.code-string { color: #ce9178; }
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.code-property { color: #9cdcfe; }
.code-flag { color: #a855f7; font-weight: 600; }
.steps {
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.step:hover {
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font-size: 1.8rem;
font-weight: 900;
color: white;
}
.step h3 {
color: var(--accent-cyan);
margin-bottom: 10px;
font-size: 1.5rem;
}
.feature-grid {
display: grid;
grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
gap: 25px;
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}
.feature-card {
background: var(--bg-secondary);
padding: 30px;
border-radius: 15px;
text-align: center;
transition: all 0.3s ease;
border: 2px solid transparent;
}
.feature-card:hover {
border-color: var(--accent-purple);
transform: translateY(-10px);
}
.feature-icon {
font-size: 3.5rem;
margin-bottom: 15px;
}
.feature-title {
font-weight: 600;
color: var(--accent-cyan);
margin-bottom: 10px;
font-size: 1.3rem;
}
.demo-container {
background: var(--bg-secondary);
border-radius: 20px;
padding: 40px;
margin: 30px 0;
}
.terminal {
background: #1e1e1e;
border-radius: 15px;
padding: 20px;
font-family: 'Fira Code', monospace;
min-height: 300px;
margin: 20px 0;
overflow-y: auto;
max-height: 500px;
}
.terminal-line {
margin: 10px 0;
}
.terminal-prompt {
color: var(--accent-green);
}
.terminal-output {
color: var(--accent-cyan);
margin-left: 20px;
}
.demo-button {
background: var(--gradient-eval);
color: white;
border: none;
padding: 15px 40px;
border-radius: 50px;
font-size: 1.1rem;
font-weight: 600;
cursor: pointer;
transition: all 0.3s ease;
display: inline-flex;
align-items: center;
gap: 10px;
margin: 10px;
}
.demo-button:hover {
transform: scale(1.05);
box-shadow: 0 10px 30px rgba(168, 85, 247, 0.4);
}
.interactive-eval {
margin: 30px 0;
}
.eval-input {
width: 100%;
background: #1e1e1e;
border: 2px solid var(--accent-purple);
border-radius: 10px;
padding: 15px;
color: var(--text-primary);
font-family: 'Fira Code', monospace;
font-size: 1rem;
margin: 10px 0;
}
.eval-input:focus {
outline: none;
border-color: var(--accent-cyan);
}
.eval-button {
background: var(--gradient-eval);
color: white;
border: none;
padding: 12px 30px;
border-radius: 10px;
font-size: 1rem;
font-weight: 600;
cursor: pointer;
transition: all 0.3s ease;
}
.eval-button:hover {
transform: scale(1.05);
}
.eval-output {
background: #1e1e1e;
border-radius: 10px;
padding: 15px;
margin-top: 15px;
min-height: 60px;
font-family: 'Fira Code', monospace;
color: var(--accent-cyan);
}
.tabs {
display: flex;
gap: 10px;
margin-bottom: 20px;
flex-wrap: wrap;
}
.tab {
padding: 12px 24px;
background: var(--bg-secondary);
border: none;
border-radius: 10px;
color: var(--text-primary);
cursor: pointer;
transition: all 0.3s ease;
font-size: 1rem;
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.tab:hover {
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.tab.active {
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color: white;
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.tab-content {
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.accordion-header {
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padding: 20px;
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border-radius: 12px;
margin: 15px 0;
transition: all 0.3s ease;
}
.accordion-header:hover {
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}
.accordion-icon {
transition: transform 0.3s ease;
font-size: 1.2rem;
}
.accordion-icon.active {
transform: rotate(180deg);
}
.accordion-content {
max-height: 0;
overflow: hidden;
transition: max-height 0.3s ease;
}
.accordion-content.active {
max-height: 2000px;
}
.accordion-body {
padding: 20px;
background: var(--bg-secondary);
border-radius: 12px;
margin-top: 5px;
}
.tip, .warning, .success, .info {
padding: 20px;
border-radius: 10px;
margin: 20px 0;
}
.tip {
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border-left: 4px solid var(--accent-blue);
}
.tip::before { content: '💡 '; font-size: 1.5rem; }
.warning {
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border-left: 4px solid var(--accent-red);
}
.warning::before { content: '⚠️ '; font-size: 1.5rem; }
.success {
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border-left: 4px solid var(--accent-green);
}
.success::before { content: '✅ '; font-size: 1.5rem; }
.info {
background: rgba(236, 72, 153, 0.1);
border-left: 4px solid var(--accent-pink);
}
.info::before { content: '🔍 '; font-size: 1.5rem; }
.quiz-container {
background: var(--bg-card);
border-radius: 20px;
padding: 40px;
margin: 30px 0;
}
.quiz-question {
margin: 30px 0;
}
.quiz-question h3 {
color: var(--accent-purple);
margin-bottom: 20px;
font-size: 1.3rem;
}
.quiz-options {
display: flex;
flex-direction: column;
gap: 15px;
}
.quiz-option {
background: var(--bg-secondary);
padding: 20px;
border-radius: 12px;
cursor: pointer;
transition: all 0.3s ease;
border: 2px solid transparent;
}
.quiz-option:hover {
border-color: var(--accent-blue);
transform: translateX(10px);
}
.quiz-option.correct {
border-color: var(--accent-green);
background: rgba(16, 185, 129, 0.1);
}
.quiz-option.incorrect {
border-color: var(--accent-red);
background: rgba(239, 68, 68, 0.1);
}
.quiz-feedback {
margin-top: 15px;
padding: 15px;
border-radius: 10px;
display: none;
}
.quiz-feedback.show {
display: block;
}
.quiz-feedback.correct {
background: rgba(16, 185, 129, 0.1);
border-left: 4px solid var(--accent-green);
}
.quiz-feedback.incorrect {
background: rgba(239, 68, 68, 0.1);
border-left: 4px solid var(--accent-red);
}
.cheat-sheet {
background: var(--gradient-eval);
border-radius: 20px;
padding: 40px;
margin: 30px 0;
color: white;
}
.cheat-grid {
display: grid;
grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
gap: 20px;
margin-top: 30px;
}
.cheat-item {
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backdrop-filter: blur(10px);
padding: 20px;
border-radius: 15px;
border: 1px solid rgba(255, 255, 255, 0.2);
}
.cheat-item h4 {
color: white;
margin-bottom: 10px;
font-weight: 600;
}
.cheat-item code {
background: rgba(0, 0, 0, 0.3);
padding: 4px 8px;
border-radius: 5px;
font-size: 0.9rem;
color: white;
}
.highlight {
color: var(--accent-yellow);
font-weight: 600;
}
.footer {
text-align: center;
padding: 40px 20px;
background: var(--bg-secondary);
margin-top: 80px;
border-radius: 20px;
}
.footer p {
color: var(--text-secondary);
margin: 10px 0;
}
.badge {
display: inline-block;
padding: 6px 12px;
background: var(--gradient-eval);
border-radius: 20px;
font-size: 0.85rem;
font-weight: 600;
margin: 5px;
}
.confetti {
position: fixed;
width: 10px;
height: 10px;
background: var(--accent-purple);
animation: confetti-fall 3s linear forwards;
z-index: 9999;
}
@keyframes confetti-fall {
to {
transform: translateY(100vh) rotate(360deg);
opacity: 0;
}
}
@media (max-width: 768px) {
.hero h1 { font-size: 2rem; }
.command-display { font-size: 1rem; padding: 15px 20px; }
.section-title { font-size: 1.8rem; }
.card { padding: 25px; }
.step { padding-left: 80px; }
.step::before { width: 50px; height: 50px; font-size: 1.5rem; }
}
</style>
</head>
<body>
<div class="progress-container">
<div class="progress-bar" id="progressBar"></div>
</div>
<div class="hero">
<div class="hero-content">
<div class="eval-icon">⚡</div>
<h1>Master node -e Command!</h1>
<div class="command-display">node -e "console.log('Hello')"</div>
<p>Run JavaScript instantly from the terminal! 🚀</p>
</div>
</div>
<div class="container">
<!-- What Is It -->
<section class="section">
<h2 class="section-title">🤔 What Is This Command?</h2>
<div class="card">
<p style="font-size: 1.2rem; margin-bottom: 20px;">
This command tells Node.js to <span class="highlight">evaluate</span> (run) JavaScript code <strong>directly</strong> from your terminal without creating a file! ⚡
</p>
<p style="margin-bottom: 20px;">
Think of it like a calculator for JavaScript! 🧮 Instead of writing code in a file and then running it, you can type JavaScript directly in your terminal and see the result instantly!
</p>
<div class="info">
<strong>Breaking It Down:</strong>
<ul style="margin-left: 30px; margin-top: 10px; line-height: 2;">
<li><code>node</code> - The Node.js runtime</li>
<li><code class="code-flag">-e</code> - Flag that means "evaluate" or "execute"</li>
<li><code class="code-string">"console.log('Hello')"</code> - The JavaScript code to run</li>
<li>Output: <code>Hello</code> appears in your terminal!</li>
</ul>
</div>
<div style="margin-top: 30px;">
<h3 style="color: var(--accent-pink); margin-bottom: 15px;">Why is this useful? 🔍</h3>
<p>Perfect for <strong>quick tests</strong>, <strong>one-liners</strong>, and <strong>debugging</strong> without creating temporary files!</p>
</div>
</div>
</section>
<!-- Why Use It -->
<section class="section">
<h2 class="section-title">✨ Why Use node -e?</h2>
<div class="card">
<div class="feature-grid">
<div class="feature-card">
<div class="feature-icon">⚡</div>
<div class="feature-title">Instant Execution</div>
<p style="color: var(--text-secondary);">No file creation needed!</p>
</div>
<div class="feature-card">
<div class="feature-icon">🧪</div>
<div class="feature-title">Quick Testing</div>
<p style="color: var(--text-secondary);">Test code snippets fast!</p>
</div>
<div class="feature-card">
<div class="feature-icon">🔧</div>
<div class="feature-title">Debugging</div>
<p style="color: var(--text-secondary);">Check values on the fly!</p>
</div>
<div class="feature-card">
<div class="feature-icon">📜</div>
<div class="feature-title">Scripting</div>
<p style="color: var(--text-secondary);">Perfect for shell scripts!</p>
</div>
<div class="feature-card">
<div class="feature-icon">🎯</div>
<div class="feature-title">One-Liners</div>
<p style="color: var(--text-secondary);">Execute single commands!</p>
</div>
<div class="feature-card">
<div class="feature-icon">🚀</div>
<div class="feature-title">Fast Prototyping</div>
<p style="color: var(--text-secondary);">Try ideas instantly!</p>
</div>
</div>
</div>
</section>
<!-- How It Works -->
<section class="section">
<h2 class="section-title">⚙️ How Does It Work?</h2>
<div class="card">
<div class="steps">
<div class="step">
<h3>Step 1: Terminal Parses Command</h3>
<p>Your shell reads the command and identifies node with the -e flag.</p>
</div>
<div class="step">
<h3>Step 2: Node.js Starts</h3>
<p>Node.js runtime initializes with the evaluate mode.</p>
</div>
<div class="step">
<h3>Step 3: Code is Parsed</h3>
<p>The JavaScript string is parsed into executable code.</p>
</div>
<div class="step">
<h3>Step 4: Code Executes</h3>
<p>Node.js runs the code in its V8 JavaScript engine.</p>
</div>
<div class="step">
<h3>Step 5: Output Displayed</h3>
<p>Results are printed to the terminal (stdout).</p>
</div>
<div class="step">
<h3>Step 6: Node.js Exits</h3>
<p>Process completes and returns to your terminal! 🎉</p>
</div>
</div>
</div>
</section>
<!-- Live Demo -->
<section class="section">
<h2 class="section-title">🎮 Interactive Demo</h2>
<div class="demo-container">
<h3 style="margin-bottom: 20px; font-size: 1.5rem;">Try It Yourself! 🚀</h3>
<div class="interactive-eval">
<label style="display: block; margin-bottom: 10px; font-weight: 600;">Type JavaScript code to evaluate:</label>
<input type="text" class="eval-input" id="evalInput" placeholder='console.log("Hello World")' value='console.log("Hello World")'>
<button class="eval-button" onclick="runEval()">⚡ Run Code</button>
<div class="eval-output" id="evalOutput">Output will appear here...</div>
</div>
<div style="margin-top: 30px;">
<h4 style="margin-bottom: 15px;">Quick Examples:</h4>
<button class="demo-button" onclick="simulateBasic()">
<span>👋</span>
<span>Basic Hello</span>
</button>
<button class="demo-button" onclick="simulateMath()">
<span>🧮</span>
<span>Math Operations</span>
</button>
<button class="demo-button" onclick="simulateDate()">
<span>📅</span>
<span>Current Date</span>
</button>
</div>
<div class="terminal" id="terminal">
<div class="terminal-line">
<span class="terminal-prompt">$</span>
<span style="color: var(--text-secondary);"> Ready to evaluate JavaScript...</span>
</div>
</div>
</div>
</section>
<!-- Code Breakdown -->
<section class="section">
<h2 class="section-title">💻 Command Variations</h2>
<div class="card">
<div class="tabs">
<button class="tab active" onclick="switchTab('basic')">Basic Usage</button>
<button class="tab" onclick="switchTab('multiline')">Multi-line</button>
<button class="tab" onclick="switchTab('modules')">With Modules</button>
<button class="tab" onclick="switchTab('advanced')">Advanced</button>
</div>
<div id="basic" class="tab-content active">
<h3 style="color: var(--accent-pink); margin-bottom: 15px;">Basic Evaluation</h3>
<div class="code-block">
<div class="code-header">
<div class="terminal-dots">
<div class="terminal-dot dot-red"></div>
<div class="terminal-dot dot-yellow"></div>
<div class="terminal-dot dot-green"></div>
</div>
<button class="copy-btn" onclick="copyCode('basic-code')">📋 Copy</button>
</div>
<pre><code id="basic-code"><span class="code-comment"># Simple console.log</span>
node -e "console.log('Hello World')"
<span class="code-comment"># Math operations</span>
node -e "console.log(2 + 2)"
<span class="code-comment"># String manipulation</span>
node -e "console.log('hello'.toUpperCase())"
<span class="code-comment"># Array operations</span>
node -e "console.log([1,2,3].map(x => x * 2))"</code></pre>
</div>
<div class="success" style="margin-top: 15px;">
<strong>Result:</strong> Instant output without creating any files!
</div>
</div>
<div id="multiline" class="tab-content">
<h3 style="color: var(--accent-pink); margin-bottom: 15px;">Multi-line Code</h3>
<div class="code-block">
<div class="code-header">
<div class="terminal-dots">
<div class="terminal-dot dot-red"></div>
<div class="terminal-dot dot-yellow"></div>
<div class="terminal-dot dot-green"></div>
</div>
<button class="copy-btn" onclick="copyCode('multiline-code')">📋 Copy</button>
</div>
<pre><code id="multiline-code"><span class="code-comment"># Use semicolons to separate statements</span>
node -e "const x = 5; const y = 10; console.log(x + y)"
<span class="code-comment"># Or use newlines with escaped quotes</span>
node -e "
const name = 'Alice';
const greeting = 'Hello, ' + name;
console.log(greeting);
"
<span class="code-comment"># Function definition and call</span>
node -e "function greet(n) { return 'Hi ' + n; } console.log(greet('Bob'))"</code></pre>
</div>
<div class="tip" style="margin-top: 15px;">
<strong>Pro Tip:</strong> Use semicolons to chain multiple statements!
</div>
</div>
<div id="modules" class="tab-content">
<h3 style="color: var(--accent-pink); margin-bottom: 15px;">Using Built-in Modules</h3>
<div class="code-block">
<div class="code-header">
<div class="terminal-dots">
<div class="terminal-dot dot-red"></div>
<div class="terminal-dot dot-yellow"></div>
<div class="terminal-dot dot-green"></div>
</div>
<button class="copy-btn" onclick="copyCode('modules-code')">📋 Copy</button>
</div>
<pre><code id="modules-code"><span class="code-comment"># File system operations</span>
node -e "const fs = require('fs'); console.log(fs.readdirSync('.'))"
<span class="code-comment"># OS information</span>
node -e "const os = require('os'); console.log(os.platform())"
<span class="code-comment"># Path operations</span>
node -e "const path = require('path'); console.log(path.resolve('.'))"
<span class="code-comment"># Crypto - generate random hex</span>
node -e "console.log(require('crypto').randomBytes(8).toString('hex'))"</code></pre>
</div>
<div class="info" style="margin-top: 15px;">
<strong>Note:</strong> You can use any built-in Node.js module with require()!
</div>
</div>
<div id="advanced" class="tab-content">
<h3 style="color: var(--accent-pink); margin-bottom: 15px;">Advanced Techniques</h3>
<div class="code-block">
<div class="code-header">
<div class="terminal-dots">
<div class="terminal-dot dot-red"></div>
<div class="terminal-dot dot-yellow"></div>
<div class="terminal-dot dot-green"></div>
</div>
<button class="copy-btn" onclick="copyCode('advanced-code')">📋 Copy</button>
</div>
<pre><code id="advanced-code"><span class="code-comment"># Access command line arguments</span>
node -e "console.log(process.argv.slice(2))" arg1 arg2
<span class="code-comment"># Use environment variables</span>
NAME=Alice node -e "console.log('Hello ' + process.env.NAME)"
<span class="code-comment"># JSON parsing</span>
node -e "console.log(JSON.parse('{\"name\":\"Bob\"}').name)"
<span class="code-comment"># Async operations (with promises)</span>
node -e "setTimeout(() => console.log('Done!'), 1000)"</code></pre>
</div>
</div>
</div>
</section>
<!-- Common Mistakes -->
<section class="section">
<h2 class="section-title">❌ Common Mistakes</h2>
<div class="card">
<div class="accordion">
<div class="accordion-item">
<div class="accordion-header" onclick="toggleAccordion(this)">
<span><strong>1. Quote Confusion</strong></span>
<span class="accordion-icon">▼</span>
</div>
<div class="accordion-content">
<div class="accordion-body">
<div class="warning">
<strong>Problem:</strong> Mixing single and double quotes incorrectly!
</div>
<div class="success" style="margin-top: 15px;">
<strong>Solution:</strong> Use double quotes outside, single inside: <code>node -e "console.log('Hello')"</code>
</div>
</div>
</div>
</div>
<div class="accordion-item">
<div class="accordion-header" onclick="toggleAccordion(this)">
<span><strong>2. Forgetting to Escape</strong></span>
<span class="accordion-icon">▼</span>
</div>
<div class="accordion-content">
<div class="accordion-body">
<div class="warning">
<strong>Problem:</strong> Special characters need escaping in some shells!
</div>
<div class="success" style="margin-top: 15px;">
<strong>Solution:</strong> Use backslashes or switch quote types: <code>node -e "console.log(\"test\")"</code>
</div>
</div>
</div>
</div>
<div class="accordion-item">
<div class="accordion-header" onclick="toggleAccordion(this)">
<span><strong>3. Expecting File Behavior</strong></span>
<span class="accordion-icon">▼</span>
</div>
<div class="accordion-content">
<div class="accordion-body">
<div class="warning">
<strong>Problem:</strong> Trying to use __dirname or __filename!
</div>
<div class="success" style="margin-top: 15px;">
<strong>Solution:</strong> These don't exist in -e mode. Use <code>process.cwd()</code> instead!
</div>
</div>
</div>
</div>
</div>
</div>
</section>
<!-- Pro Tips -->
<section class="section">
<h2 class="section-title">🚀 Pro Tips</h2>
<div class="card">
<div class="tip">
<strong>Use -p for printing</strong> - <code>node -p "2+2"</code> automatically prints the result (no console.log needed)!
</div>
<div class="tip">
<strong>Chain with pipes</strong> - Combine with other commands: <code>echo '{"name":"Alice"}' | node -e "console.log(JSON.parse(require('fs').readFileSync(0)))"</code>
</div>
<div class="tip">
<strong>Create aliases</strong> - Add to .bashrc: <code>alias njs='node -e'</code> for shorter commands!
</div>
<div class="tip">
<strong>Use for quick calculations</strong> - <code>node -p "Math.sqrt(144)"</code> is faster than opening a calculator!
</div>
<div class="tip">
<strong>Test regex patterns</strong> - <code>node -e "console.log(/\d+/.test('abc123'))"</code> for quick regex testing!
</div>
<div class="tip">
<strong>Generate random data</strong> - <code>node -p "Math.random().toString(36).substr(2, 9)"</code> for random strings!
</div>
</div>
</section>
<!-- Quiz -->
<section class="section">
<h2 class="section-title">🎯 Knowledge Check Quiz</h2>
<div class="quiz-container">
<p style="margin-bottom: 30px; font-size: 1.1rem;">Test your understanding! 🧠</p>
<div class="quiz-question">
<h3>Question 1: What does the -e flag do?</h3>
<div class="quiz-options">
<div class="quiz-option" onclick="checkAnswer(this, false, 1)">A) Enables error messages</div>
<div class="quiz-option" onclick="checkAnswer(this, true, 1)">B) Evaluates JavaScript code from command line</div>
<div class="quiz-option" onclick="checkAnswer(this, false, 1)">C) Exits the program</div>
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<div class="quiz-feedback" id="feedback1"></div>
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<div class="quiz-question">
<h3>Question 2: Which is correct syntax?</h3>
<div class="quiz-options">
<div class="quiz-option" onclick="checkAnswer(this, false, 2)">A) node -e 'console.log("Hello")'</div>
<div class="quiz-option" onclick="checkAnswer(this, true, 2)">B) node -e "console.log('Hello')"</div>
<div class="quiz-option" onclick="checkAnswer(this, false, 2)">C) Both are correct</div>
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<h3>Question 3: What's the difference between -e and -p?</h3>
<div class="quiz-options">
<div class="quiz-option" onclick="checkAnswer(this, false, 3)">A) No difference</div>
<div class="quiz-option" onclick="checkAnswer(this, true, 3)">B) -p automatically prints the result, -e requires console.log</div>
<div class="quiz-option" onclick="checkAnswer(this, false, 3)">C) -p is for production mode</div>
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<h3 style="color: var(--accent-green); font-size: 1.5rem;">🎉 Quiz Complete!</h3>
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</div>
</section>
<!-- Summary Card -->
<section class="section">
<h2 class="section-title">📚 Quick Reference</h2>
<div class="cheat-sheet">
<h3 style="margin-bottom: 20px; font-size: 2rem;">node -e Cheat Sheet! 🔖</h3>
<div class="cheat-grid">
<div class="cheat-item">
<h4>⚡ Basic Eval</h4>
<p><code>node -e "console.log('Hi')"</code></p>
<p style="font-size: 0.85rem; margin-top: 5px;">Run JS code</p>
</div>
<div class="cheat-item">
<h4>📤 Auto Print</h4>
<p><code>node -p "2+2"</code></p>
<p style="font-size: 0.85rem; margin-top: 5px;">Print result</p>
</div>
<div class="cheat-item">
<h4>🧮 Math</h4>
<p><code>node -e "console.log(Math.PI)"</code></p>
<p style="font-size: 0.85rem; margin-top: 5px;">Quick calculations</p>
</div>
<div class="cheat-item">
<h4>📦 Modules</h4>
<p><code>node -e "require('os').platform()"</code></p>
<p style="font-size: 0.85rem; margin-top: 5px;">Use built-ins</p>
</div>
<div class="cheat-item">
<h4>🔗 Multiple Lines</h4>
<p><code>node -e "const x=5; console.log(x)"</code></p>
<p style="font-size: 0.85rem; margin-top: 5px;">Use semicolons</p>
</div>
<div class="cheat-item">
<h4>🌍 Environment</h4>
<p><code>node -e "console.log(process.env)"</code></p>
<p style="font-size: 0.85rem; margin-top: 5px;">Access env vars</p>
</div>
<div class="cheat-item">
<h4>📝 JSON Parse</h4>
<p><code>node -e "JSON.parse(...)"</code></p>
<p style="font-size: 0.85rem; margin-top: 5px;">Parse JSON</p>
</div>
<div class="cheat-item">
<h4>🎲 Random</h4>
<p><code>node -p "Math.random()"</code></p>
<p style="font-size: 0.85rem; margin-top: 5px;">Generate randoms</p>
</div>
</div>
</div>
</section>
<!-- Footer -->
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<h2 style="font-size: 2rem; margin-bottom: 20px; color: var(--accent-pink);">🎉 Congratulations!</h2>
<p style="font-size: 1.2rem; margin-bottom: 20px;">You now understand <strong>node -e</strong>! 🚀</p>
<div style="margin: 30px 0;">
<span class="badge">⚡ Eval Master</span>
<span class="badge">🧪 One-Liner Pro</span>
<span class="badge">🚀 Node.js Expert</span>
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<p style="color: var(--text-secondary); font-size: 0.9rem;">Made with ❤️ for developers learning Node.js</p>
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