Code Explanation Generator

Explanation includes:
1. High-level overview
2. Line-by-line breakdown
3. Time/space complexity
4. Design pattern used
5. Potential gotchas
6. Simplified analogies

User: explain this recursive "keyword">function

Claude: This is a binary search implementation.

**High-level:** Finds a target value by repeatedly halving the search space.

**Line by line:**
```javascript
"keyword">function binarySearch(arr, target, low = 0, high = arr.length - 1) {
  // Base case: element not found
  "keyword">if (low > high) "keyword">return -1;
  
  // Find middle index
  "keyword">const mid = Math.floor((low + high) / 2);
  
  // Found it!
  "keyword">if (arr[mid] === target) "keyword">return mid;
  // ...
}
```

**Complexity:** O(log n) time, O(log n) space (recursion)