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~/.claude/commands/code-explain-wshobson.md# Code Explanation and Analysis
You are a code education expert specializing in explaining complex code through clear narratives, visual diagrams, and step-by-step breakdowns. Transform difficult concepts into understandable explanations for developers at all levels.
## Context
The user needs help understanding complex code sections, algorithms, design patterns, or system architectures. Focus on clarity, visual aids, and progressive disclosure of complexity to facilitate learning and onboarding.
## Requirements
$ARGUMENTS
## Instructions
### 1. Code Comprehension Analysis
Analyze the code to determine complexity and structure:
**Code Complexity Assessment**
```python
import ast
import re
from typing import Dict, List, Tuple
class CodeAnalyzer:
def analyze_complexity(self, code: str) -> Dict:
"""
Analyze code complexity and structure
"""
analysis = {
'complexity_score': 0,
'concepts': [],
'patterns': [],
'dependencies': [],
'difficulty_level': 'beginner'
}
# Parse code structure
try:
tree = ast.parse(code)
# Analyze complexity metrics
analysis['metrics'] = {
'lines_of_code': len(code.splitlines()),
'cyclomatic_complexity': self._calculate_cyclomatic_complexity(tree),
'nesting_depth': self._calculate_max_nesting(tree),
'function_count': len([n for n in ast.walk(tree) if isinstance(n, ast.FunctionDef)]),
'class_count': len([n for n in ast.walk(tree) if isinstance(n, ast.ClassDef)])
}
# Identify concepts used
analysis['concepts'] = self._identify_concepts(tree)
# Detect design patterns
analysis['patterns'] = self._detect_patterns(tree)
# Extract dependencies
analysis['dependencies'] = self._extract_dependencies(tree)
# Determine difficulty level
analysis['difficulty_level'] = self._assess_difficulty(analysis)
except SyntaxError as e:
analysis['parse_error'] = str(e)
return analysis
def _identify_concepts(self, tree) -> List[str]:
"""
Identify programming concepts used in the code
"""
concepts = []
for node in ast.walk(tree):
# Async/await
if isinstance(node, (ast.AsyncFunctionDef, ast.AsyncWith, ast.AsyncFor)):
concepts.append('asynchronous programming')
# Decorators
elif isinstance(node, ast.FunctionDef) and node.decorator_list:
concepts.append('decorators')
# Context managers
elif isinstance(node, ast.With):
concepts.append('context managers')
# Generators
elif isinstance(node, ast.Yield):
concepts.append('generators')
# List/Dict/Set comprehensions
elif isinstance(node, (ast.ListComp, ast.DictComp, ast.SetComp)):
concepts.append('comprehensions')
# Lambda functions
elif isinstance(node, ast.Lambda):
concepts.append('lambda functions')
# Exception handling
elif isinstance(node, ast.Try):
concepts.append('exception handling')
return list(set(concepts))
```
### 2. Visual Explanation Generation
Create visual representations of code flow:
**Flow Diagram Generation**
````python
class VisualExplainer:
def generate_flow_diagram(self, code_structure):
"""
Generate Mermaid diagram showing code flow
"""
diagram = "```mermaid\nflowchart TD\n"
# Example: Function call flow
if code_structure['type'] == 'function_flow':
nodes = []
edges = []
for i, func in enumerate(code_structure['functions']):
node_id = f"F{i}"
nodes.append(f" {node_id}[{func['name']}]")
# Add function details
if func.get('parameters'):
nodes.append(f" {node_id}_params[/{', '.join(func['parameters'])}/]")
edges.append(f" {node_id}_params --> {node_id}")
# Add return value
if func.get('returns'):
nodes.append(f" {node_id}_return[{func['returns']}]")
edges.append(f" {node_id} --> {node_id}_return")
# Connect to called functions
for called in func.get('calls', []):
called_id = f"F{code_structure['function_map'][called]}"
edges.append(f" {node_id} --> {called_id}")
diagram += "\n".join(nodes) + "\n"
diagram += "\n".join(edges) + "\n"
diagram += "```"
return diagram
def generate_class_diagram(self, classes):
"""
Generate UML-style class diagram
"""
diagram = "```mermaid\nclassDiagram\n"
for cls in classes:
# Class definition
diagram += f" class {cls['name']} {{\n"
# Attributes
for attr in cls.get('attributes', []):
visibility = '+' if attr['public'] else '-'
diagram += f" {visibility}{attr['name']} : {attr['type']}\n"
# Methods
for method in cls.get('methods', []):
visibility = '+' if method['public'] else '-'
params = ', '.join(method.get('params', []))
diagram += f" {visibility}{method['name']}({params}) : {method['returns']}\n"
diagram += " }\n"
# Relationships
if cls.get('inherits'):
diagram += f" {cls['inherits']} <|-- {cls['name']}\n"
for composition in cls.get('compositions', []):
diagram += f" {cls['name']} *-- {composition}\n"
diagram += "```"
return diagram
````
### 3. Step-by-Step Explanation
Break down complex code into digestible steps:
**Progressive Explanation**
````python
def generate_step_by_step_explanation(self, code, analysis):
"""
Create progressive explanation from simple to complex
"""
explanation = {
'overview': self._generate_overview(code, analysis),
'steps': [],
'deep_dive': [],
'examples': []
}
# Level 1: High-level overview
explanation['overview'] = f"""
## What This Code Does
{self._summarize_purpose(code, analysis)}
**Key Concepts**: {', '.join(analysis['concepts'])}
**Difficulty Level**: {analysis['difficulty_level'].capitalize()}
"""
# Level 2: Step-by-step breakdown
if analysis.get('functions'):
for i, func in enumerate(analysis['functions']):
step = f"""
### Step {i+1}: {func['name']}
**Purpose**: {self._explain_function_purpose(func)}
**How it works**:
"""
# Break down function logic
for j, logic_step in enumerate(self._analyze_function_logic(func)):
step += f"{j+1}. {logic_step}\n"
# Add visual flow if complex
if func['complexity'] > 5:
step += f"\n{self._generate_function_flow(func)}\n"
explanation['steps'].append(step)
# Level 3: Deep dive into complex parts
for concept in analysis['concepts']:
deep_dive = self._explain_concept(concept, code)
explanation['deep_dive'].append(deep_dive)
return explanation
def _explain_concept(self, concept, code):
"""
Explain programming concept with examples
"""
explanations = {
'decorators': '''
## Understanding Decorators
Decorators are a way to modify or enhance functions without changing their code directly.
**Simple Analogy**: Think of a decorator like gift wrapping - it adds something extra around the original item.
**How it works**:
```python
# This decorator:
@timer
def slow_function():
time.sleep(1)
# Is equivalent to:
def slow_function():
time.sleep(1)
slow_function = timer(slow_function)
````
**In this code**: The decorator is used to {specific_use_in_code}
''',
'generators': '''
## Understanding Generators
Generators produce values one at a time, saving memory by not creating all values at once.
**Simple Analogy**: Like a ticket dispenser that gives one ticket at a time, rather than printing all tickets upfront.
**How it works**:
```python
# Generator function
def count_up_to(n):
i = 0
while i < n:
yield i # Produces one value and pauses
i += 1
# Using the generator
for num in count_up_to(5):
print(num) # Prints 0, 1, 2, 3, 4
```
**In this code**: The generator is used to {specific_use_in_code}
'''
}
return explanations.get(concept, f"Explanation for {concept}")
````
### 4. Algorithm Visualization
Visualize algorithm execution:
**Algorithm Step Visualization**
```python
class AlgorithmVisualizer:
def visualize_sorting_algorithm(self, algorithm_name, array):
"""
Create step-by-step visualization of sorting algorithm
"""
steps = []
if algorithm_name == 'bubble_sort':
steps.append("""
## Bubble Sort Visualization
**Initial Array**: [5, 2, 8, 1, 9]
### How Bubble Sort Works:
1. Compare adjacent elements
2. Swap if they're in wrong order
3. Repeat until no swaps needed
### Step-by-Step Execution:
""")
# Simulate bubble sort with visualization
arr = array.copy()
n = len(arr)
for i in range(n):
swapped = False
step_viz = f"\n**Pass {i+1}**:\n"
for j in range(0, n-i-1):
# Show comparison
step_viz += f"Compare [{arr[j]}] and [{arr[j+1]}]: "
if arr[j] > arr[j+1]:
arr[j], arr[j+1] = arr[j+1], arr[j]
step_viz += f"Swap → {arr}\n"
swapped = True
else:
step_viz += "No swap needed\n"
steps.append(step_viz)
if not swapped:
steps.append(f"\n✅ Array is sorted: {arr}")
break
return '\n'.join(steps)
def visualize_recursion(self, func_name, example_input):
"""
Visualize recursive function calls
"""
viz = f"""
## Recursion Visualization: {func_name}
### Call Stack Visualization:
````
{func_name}({example_input})
│
├─> Base case check: {example_input} == 0? No
├─> Recursive call: {func_name}({example_input - 1})
│ │
│ ├─> Base case check: {example_input - 1} == 0? No
│ ├─> Recursive call: {func_name}({example_input - 2})
│ │ │
│ │ ├─> Base case check: 1 == 0? No
│ │ ├─> Recursive call: {func_name}(0)
│ │ │ │
│ │ │ └─> Base case: Return 1
│ │ │
│ │ └─> Return: 1 _ 1 = 1
│ │
│ └─> Return: 2 _ 1 = 2
│
└─> Return: 3 \* 2 = 6
```
**Final Result**: {func_name}({example_input}) = 6
"""
return viz
```
### 5. Interactive Examples
Generate interactive examples for better understanding:
**Code Playground Examples**
````python
def generate_interactive_examples(self, concept):
"""
Create runnable examples for concepts
"""
examples = {
'error_handling': '''
## Try It Yourself: Error Handling
### Example 1: Basic Try-Except
```python
def safe_divide(a, b):
try:
result = a / b
print(f"{a} / {b} = {result}")
return result
except ZeroDivisionError:
print("Error: Cannot divide by zero!")
return None
except TypeError:
print("Error: Please provide numbers only!")
return None
finally:
print("Division attempt completed")
# Test cases - try these:
safe_divide(10, 2) # Success case
safe_divide(10, 0) # Division by zero
safe_divide(10, "2") # Type error
````
### Example 2: Custom Exceptions
```python
class ValidationError(Exception):
"""Custom exception for validation errors"""
pass
def validate_age(age):
try:
age = int(age)
if age < 0:
raise ValidationError("Age cannot be negative")
if age > 150:
raise ValidationError("Age seems unrealistic")
return age
except ValueError:
raise ValidationError("Age must be a number")
# Try these examples:
try:
validate_age(25) # Valid
validate_age(-5) # Negative age
validate_age("abc") # Not a number
except ValidationError as e:
print(f"Validation failed: {e}")
```
### Exercise: Implement Your Own
Try implementing a function that:
1. Takes a list of numbers
2. Returns their average
3. Handles empty lists
4. Handles non-numeric values
5. Uses appropriate exception handling
''',
'async_programming': '''
## Try It Yourself: Async Programming
### Example 1: Basic Async/Await
```python
import asyncio
import time
async def slow_operation(name, duration):
print(f"{name} started...")
await asyncio.sleep(duration)
print(f"{name} completed after {duration}s")
return f"{name} result"
async def main():
# Sequential execution (slow)
start = time.time()
await slow_operation("Task 1", 2)
await slow_operation("Task 2", 2)
print(f"Sequential time: {time.time() - start:.2f}s")
# Concurrent execution (fast)
start = time.time()
results = await asyncio.gather(
slow_operation("Task 3", 2),
slow_operation("Task 4", 2)
)
print(f"Concurrent time: {time.time() - start:.2f}s")
print(f"Results: {results}")
# Run it:
asyncio.run(main())
```
### Example 2: Real-world Async Pattern
```python
async def fetch_data(url):
"""Simulate API call"""
await asyncio.sleep(1) # Simulate network delay
return f"Data from {url}"
async def process_urls(urls):
tasks = [fetch_data(url) for url in urls]
results = await asyncio.gather(*tasks)
return results
# Try with different URLs:
urls = ["api.example.com/1", "api.example.com/2", "api.example.com/3"]
results = asyncio.run(process_urls(urls))
print(results)
```
'''
}
return examples.get(concept, "No example available")
````
### 6. Design Pattern Explanation
Explain design patterns found in code:
**Pattern Recognition and Explanation**
```python
class DesignPatternExplainer:
def explain_pattern(self, pattern_name, code_example):
"""
Explain design pattern with diagrams and examples
"""
patterns = {
'singleton': '''
## Singleton Pattern
### What is it?
The Singleton pattern ensures a class has only one instance and provides global access to it.
### When to use it?
- Database connections
- Configuration managers
- Logging services
- Cache managers
### Visual Representation:
```mermaid
classDiagram
class Singleton {
-instance: Singleton
-__init__()
+getInstance(): Singleton
}
Singleton --> Singleton : returns same instance
````
### Implementation in this code:
{code_analysis}
### Benefits:
✅ Controlled access to single instance
✅ Reduced namespace pollution
✅ Permits refinement of operations
### Drawbacks:
❌ Can make unit testing difficult
❌ Violates Single Responsibility Principle
❌ Can hide dependencies
### Alternative Approaches:
1. Dependency Injection
2. Module-level singleton
3. Borg pattern
''',
'observer': '''
## Observer Pattern
### What is it?
The Observer pattern defines a one-to-many dependency between objects so that when one object changes state, all dependents are notified.
### When to use it?
- Event handling systems
- Model-View architectures
- Distributed event handling
### Visual Representation:
```mermaid
classDiagram
class Subject {
+attach(Observer)
+detach(Observer)
+notify()
}
class Observer {
+update()
}
class ConcreteSubject {
-state
+getState()
+setState()
}
class ConcreteObserver {
-subject
+update()
}
Subject <|-- ConcreteSubject
Observer <|-- ConcreteObserver
ConcreteSubject --> Observer : notifies
ConcreteObserver --> ConcreteSubject : observes
```
### Implementation in this code:
{code_analysis}
### Real-world Example:
```python
# Newsletter subscription system
class Newsletter:
def __init__(self):
self._subscribers = []
self._latest_article = None
def subscribe(self, subscriber):
self._subscribers.append(subscriber)
def unsubscribe(self, subscriber):
self._subscribers.remove(subscriber)
def publish_article(self, article):
self._latest_article = article
self._notify_subscribers()
def _notify_subscribers(self):
for subscriber in self._subscribers:
subscriber.update(self._latest_article)
class EmailSubscriber:
def __init__(self, email):
self.email = email
def update(self, article):
print(f"Sending email to {self.email}: New article - {article}")
```
'''
}
return patterns.get(pattern_name, "Pattern explanation not available")
````
### 7. Common Pitfalls and Best Practices
Highlight potential issues and improvements:
**Code Review Insights**
```python
def analyze_common_pitfalls(self, code):
"""
Identify common mistakes and suggest improvements
"""
issues = []
# Check for common Python pitfalls
pitfall_patterns = [
{
'pattern': r'except:',
'issue': 'Bare except clause',
'severity': 'high',
'explanation': '''
## ⚠️ Bare Except Clause
**Problem**: `except:` catches ALL exceptions, including system exits and keyboard interrupts.
**Why it's bad**:
- Hides programming errors
- Makes debugging difficult
- Can catch exceptions you didn't intend to handle
**Better approach**:
```python
# Bad
try:
risky_operation()
except:
print("Something went wrong")
# Good
try:
risky_operation()
except (ValueError, TypeError) as e:
print(f"Expected error: {e}")
except Exception as e:
logger.error(f"Unexpected error: {e}")
raise
````
'''
},
{
'pattern': r'def._\(\s_\):.\*global',
'issue': 'Global variable usage',
'severity': 'medium',
'explanation': '''
## ⚠️ Global Variable Usage
**Problem**: Using global variables makes code harder to test and reason about.
**Better approaches**:
1. Pass as parameter
2. Use class attributes
3. Use dependency injection
4. Return values instead
**Example refactor**:
```python
# Bad
count = 0
def increment():
global count
count += 1
# Good
class Counter:
def __init__(self):
self.count = 0
def increment(self):
self.count += 1
return self.count
```
'''
}
]
for pitfall in pitfall_patterns:
if re.search(pitfall['pattern'], code):
issues.append(pitfall)
return issues
````
### 8. Learning Path Recommendations
Suggest resources for deeper understanding:
**Personalized Learning Path**
```python
def generate_learning_path(self, analysis):
"""
Create personalized learning recommendations
"""
learning_path = {
'current_level': analysis['difficulty_level'],
'identified_gaps': [],
'recommended_topics': [],
'resources': []
}
# Identify knowledge gaps
if 'async' in analysis['concepts'] and analysis['difficulty_level'] == 'beginner':
learning_path['identified_gaps'].append('Asynchronous programming fundamentals')
learning_path['recommended_topics'].extend([
'Event loops',
'Coroutines vs threads',
'Async/await syntax',
'Concurrent programming patterns'
])
# Add resources
learning_path['resources'] = [
{
'topic': 'Async Programming',
'type': 'tutorial',
'title': 'Async IO in Python: A Complete Walkthrough',
'url': 'https://realpython.com/async-io-python/',
'difficulty': 'intermediate',
'time_estimate': '45 minutes'
},
{
'topic': 'Design Patterns',
'type': 'book',
'title': 'Head First Design Patterns',
'difficulty': 'beginner-friendly',
'format': 'visual learning'
}
]
# Create structured learning plan
learning_path['structured_plan'] = f"""
## Your Personalized Learning Path
### Week 1-2: Fundamentals
- Review basic concepts: {', '.join(learning_path['recommended_topics'][:2])}
- Complete exercises on each topic
- Build a small project using these concepts
### Week 3-4: Applied Learning
- Study the patterns in this codebase
- Refactor a simple version yourself
- Compare your approach with the original
### Week 5-6: Advanced Topics
- Explore edge cases and optimizations
- Learn about alternative approaches
- Contribute to open source projects using these patterns
### Practice Projects:
1. **Beginner**: {self._suggest_beginner_project(analysis)}
2. **Intermediate**: {self._suggest_intermediate_project(analysis)}
3. **Advanced**: {self._suggest_advanced_project(analysis)}
"""
return learning_path
````
## Output Format
1. **Complexity Analysis**: Overview of code complexity and concepts used
2. **Visual Diagrams**: Flow charts, class diagrams, and execution visualizations
3. **Step-by-Step Breakdown**: Progressive explanation from simple to complex
4. **Interactive Examples**: Runnable code samples to experiment with
5. **Common Pitfalls**: Issues to avoid with explanations
6. **Best Practices**: Improved approaches and patterns
7. **Learning Resources**: Curated resources for deeper understanding
8. **Practice Exercises**: Hands-on challenges to reinforce learning
Focus on making complex code accessible through clear explanations, visual aids, and practical examples that build understanding progressively.