Code Improvement

Identify opportunities to improve existing code quality, performance, and maintainability.

Improvement Categories

Refactoring

• Extract methods/functions
• Simplify conditionals
• Remove duplication
• Improve naming
• Reduce complexity

Performance

• Algorithm optimization
• Caching opportunities
• Query optimization
• Memory efficiency
• Lazy loading

Modernization

• Update deprecated APIs
• Use newer language features
• Adopt current best practices
• Improve type safety

Architecture

• Better separation of concerns
• Improved abstraction
• Cleaner interfaces
• Reduced coupling

Refactoring Patterns

Extract Method

# Before: Long function with multiple responsibilities
def process_order(order):
    # Validate
    if not order.items:
        raise ValueError("Empty order")
    if not order.user.is_active:
        raise ValueError("Inactive user")

    # Calculate totals
    subtotal = sum(item.price * item.quantity for item in order.items)
    tax = subtotal * 0.1
    total = subtotal + tax

    # Save
    order.subtotal = subtotal
    order.tax = tax
    order.total = total
    order.save()

# After: Extracted methods
def process_order(order):
    validate_order(order)
    calculate_totals(order)
    order.save()

def validate_order(order):
    if not order.items:
        raise ValueError("Empty order")
    if not order.user.is_active:
        raise ValueError("Inactive user")

def calculate_totals(order):
    order.subtotal = sum(item.price * item.quantity for item in order.items)
    order.tax = order.subtotal * TAX_RATE
    order.total = order.subtotal + order.tax

Replace Conditional with Polymorphism

# Before: Type-checking conditional
def calculate_area(shape):
    if shape.type == 'circle':
        return math.pi * shape.radius ** 2
    elif shape.type == 'rectangle':
        return shape.width * shape.height
    elif shape.type == 'triangle':
        return 0.5 * shape.base * shape.height

# After: Polymorphic method
class Circle:
    def area(self):
        return math.pi * self.radius ** 2

class Rectangle:
    def area(self):
        return self.width * self.height

Introduce Parameter Object

# Before: Too many parameters
def create_user(name, email, age, address, city, country, phone):
    ...

# After: Parameter object
@dataclass
class UserData:
    name: str
    email: str
    age: int
    address: str
    city: str
    country: str
    phone: str

def create_user(data: UserData):
    ...

Performance Improvements

Add Caching

# Before: Repeated expensive computation
def get_user_stats(user_id):
    # Complex queries every time
    return calculate_stats(user_id)

# After: With caching
from functools import lru_cache

@lru_cache(maxsize=100)
def get_user_stats(user_id):
    return calculate_stats(user_id)

Batch Database Operations

# Before: N+1 queries
def get_order_details(order_ids):
    orders = []
    for order_id in order_ids:
        order = Order.query.get(order_id)  # N queries
        orders.append(order)
    return orders

# After: Single query
def get_order_details(order_ids):
    return Order.query.filter(Order.id.in_(order_ids)).all()

Lazy Loading

# Before: Load everything upfront
class Report:
    def __init__(self):
        self.data = self._load_all_data()  # Expensive

# After: Load on demand
class Report:
    def __init__(self):
        self._data = None

    @property
    def data(self):
        if self._data is None:
            self._data = self._load_all_data()
        return self._data

Improvement Output Format

## Improvement Suggestions: [File/Module Name]

### High Impact
Improvements with significant benefit, relatively low effort.

#### 1. [Title]
**Current:**
```python
current_code()

Suggested:

improved_code()

Benefits:

• [Benefit 1]
• [Benefit 2]

Effort: Low/Medium/High

Medium Impact

Worth doing but lower priority.

1. [Title]

...

Future Considerations

Ideas for later, not urgent.

• [Idea 1]
• [Idea 2]

## When NOT to Suggest Improvements

Avoid suggesting changes that:
- Add complexity without clear benefit
- Are purely stylistic preferences
- Would require large rewrites for small gains
- Are speculative ("might be useful someday")
- Break working code for theoretical improvements

Focus on improvements that:
- Fix actual problems (bugs, performance, security)
- Significantly improve maintainability
- Have clear, measurable benefits
- Can be done incrementally