Code Conventions - Code Style Persona Skill

Code Conventions - Code Style Persona

Role

Guide how to write code:

Maintain consistent code style
Write readable code
Create maintainable structure

General Principles

Early Return Pattern

Prefer early returns over nested conditions for better readability.

Size Limits

| Target | Limit | When Exceeded | |--------|-------|---------------| | Function/Method | 50 lines | Split | | File/Class | 200 lines | Split into modules | | Nesting depth | 3 levels | Apply early return |

TypeScript Conventions

Naming

| Type | Pattern | Example | |------|---------|---------| | Class/Interface/Type | PascalCase | OrderService, UserEntity | | Function/Variable | camelCase | calculateTotal, userName | | Constant | SCREAMING_SNAKE | MAX_RETRY_COUNT | | File | kebab-case or camelCase | order-service.ts | | Boolean | is/has/can prefix | isActive, hasPermission |

Best Practices

Use arrow functions when possible
Prefer const over let, avoid var
Always declare explicit types
Use interface for object shapes, type for unions/intersections
Prefer unknown over any

Avoid

❌ utils.ts, helpers.ts, common.ts, shared.ts

Python Conventions (PEP-8)

Naming

| Type | Pattern | Example | |------|---------|---------| | Class | PascalCase | OrderService, UserEntity | | Function/Variable | snake_case | calculate_total, user_name | | Constant | SCREAMING_SNAKE | MAX_RETRY_COUNT | | Module/File | snake_case | order_service.py | | Private | leading underscore | _internal_method |

Best Practices

Maximum line length: 79 characters (code), 72 (docstrings)
Use 4 spaces for indentation (no tabs)
Two blank lines between top-level definitions
One blank line between method definitions
Use type hints (PEP 484)
Use docstrings for public modules, functions, classes, methods

Import Order (PEP-8)

# 1. Standard library
import os
import sys

# 2. Third-party
import requests
import numpy as np

# 3. Local application
from myapp import utils

Avoid

❌ utils.py, helpers.py, common.py, shared.py

Java Conventions

Naming

| Type | Pattern | Example | |------|---------|---------| | Class/Interface | PascalCase | OrderService, UserEntity | | Method/Variable | camelCase | calculateTotal, userName | | Constant | SCREAMING_SNAKE | MAX_RETRY_COUNT | | Package | lowercase | com.example.order | | File | Same as class name | OrderService.java |

Best Practices

One public class per file
Use final for immutable variables
Prefer composition over inheritance
Use interfaces for abstraction
Follow JavaDoc conventions for documentation
Use Optional instead of null for return values

Avoid

❌ Utils.java, Helpers.java, Common.java, Shared.java

Checklist

When Writing Code

[ ] Is function/method under 50 lines?
[ ] Is file/class under 200 lines?
[ ] Is nesting under 3 levels?
[ ] Is early return applied?
[ ] Is naming following language conventions?
[ ] Are types/type hints declared?

Before PR

[ ] Consistent code style maintained
[ ] Unnecessary comments removed
[ ] Error handling appropriate
[ ] Linter/formatter passed

Anti-Patterns

Magic Numbers: Using meaningless numbers directly
God Function/Class: Giant function/class that does everything
Callback Hell / Nested Conditionals: Deep nesting
Copy-Paste Code: Duplicated code
Generic Naming: utils, helpers, common, shared, misc

Agent Skills: Code Conventions - Code Style Persona

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