coding-standards

Coding Standards Skill

Level 1: Quick Start (5 minutes)

What You'll Learn

Apply essential coding standards for clean, maintainable code that follows industry best practices.

Core Principles

• Consistency: Follow established style guides (PEP 8, Airbnb, Google)
• Readability: Write self-documenting code with clear naming
• Maintainability: Keep functions small (<50 lines), files focused (<500 lines)
• Quality: Enforce standards with linters and formatters

Quick Reference

# ✅ Good: Clear naming, single responsibility
def calculate_user_discount(user: User, order: Order) -> Decimal:
    """Calculate discount based on user tier and order total."""
    if user.tier == "premium":
        return order.total * Decimal("0.15")
    return order.total * Decimal("0.05")

# ❌ Bad: Unclear naming, mixed concerns
def calc(u, o):
    d = 0.15 if u.t == "p" else 0.05
    save_to_db(u, o, d)  # Side effect!
    return o.t * d

Essential Checklist

• Follow language-specific style guide
• Use meaningful, descriptive names
• Limit function complexity (cyclomatic < 10)
• Configure linter and formatter
• Add pre-commit hooks

Common Pitfalls

• Inconsistent naming conventions within a project
• Functions that do too many things
• Missing or outdated documentation
• Skipping code reviews

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Level 2: Implementation (30 minutes)

Deep Dive Topics

1. Code Style and Formatting

Naming Conventions by Language:

// TypeScript/JavaScript
class UserService {}           // PascalCase for classes
const getUserById = () => {}   // camelCase for functions
const API_ENDPOINT = "..."     // UPPER_SNAKE_CASE for constants

# Python
class UserService:              # PascalCase for classes
def get_user_by_id():          # snake_case for functions
API_ENDPOINT = "..."           # UPPER_SNAKE_CASE for constants

File Organization:

src/
├── models/           # Data models and types
├── services/         # Business logic (max 500 lines/file)
├── controllers/      # Request handlers
├── utils/           # Shared utilities
└── config/          # Configuration