Use the Narrowest Possible Scope for any Types

Overview

If you must use any, contain the damage.

any is contagious - it spreads through your code. Keep it as narrowly scoped as possible to limit its impact on type safety.

When to Use This Skill

• Forced to use any for some reason
• Working with untyped third-party code
• Dealing with complex type errors
• Migrating JavaScript to TypeScript
• Reviewing code that uses any

The Iron Rule