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name: coding-practices description: Code quality practices: error handling, validation, logging, and DRY. Use when writing or reviewing code.

Coding Practices

Guidelines for writing maintainable, robust, and self-documenting code.

Quick Start

Copy// Self-documenting with proper error handling
function createUser(email: string, age: number): User {
  if (!email.includes("@")) throw new Error("Invalid email");
  if (age < 0 || age > 150) throw new Error("Invalid age");
  return { email, age };
}

Key Principles

• Use meaningful names (self-documenting code)
• Comments explain "why", not "what"
• DRY: abstract when used 3+ times
• Validate all input data
• Handle all error cases with proper Error objects
• Never ignore errors
• Use named constants instead of magic values
• Avoid circular dependencies

References

See rules.md for complete guidelines with examples.