// JavaScript
function add(a, b) {
  return a + b;
}

const user = {
  name: 'John',
  age: 30
};

// TypeScript
function add(a: number, b: number): number {
  return a + b;
}

interface User {
  name: string;
  age: number;
}

const user: User = {
  name: 'John',
  age: 30
};

# Python
def greet(name):
    return f"Hello, {name}!"

numbers = [1, 2, 3, 4, 5]
squares = [x**2 for x in numbers]
filtered = list(filter(lambda x: x > 10, squares))

// JavaScript
function greet(name) {
  return `Hello, ${name}!`;
}

const numbers = [1, 2, 3, 4, 5];
const squares = numbers.map(x => x ** 2);
const filtered = squares.filter(x => x > 10);

// React
function Counter() {
  const [count, setCount] = useState(0);
  
  return (
    <button onClick={() => setCount(count + 1)}>
      Count: {count}
    </button>
  );
}

<!-- Vue 3 -->
<template>
  <button @click="count++">
    Count: {{ count }}
  </button>
</template>

<script setup>
import { ref } from 'vue';
const count = ref(0);
</script>

1. UNDERSTAND source code
   - Logic flow
   - Data structures
   - Dependencies

2. IDENTIFY equivalents
   - Language constructs
   - Standard library
   - Idioms

3. TRANSLATE structure
   - Maintain logic
   - Adapt syntax
   - Use target idioms

4. ADAPT patterns
   - Error handling
   - Async patterns
   - Type systems

5. VERIFY
   - Same output
   - Same behavior
   - No logic changes