TY
TypeScript Defaults
Core TypeScript coding conventions
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TypeScriptCategory
Style Guide
Rules
balanced
- Use TypeScript strict mode with `strict: true` in `tsconfig.json` — enables `strictNullChecks`, `noImplicitAny`, and other safety checks.
- Use `const` by default; `let` only when reassignment is needed. Never use `var`.
- Use `interface` for object shapes that may be extended and `type` for unions, intersections, and mapped types.
- Prefer `unknown` over `any` — it forces type narrowing before use and catches bugs at compile time.
- Avoid `any` — use `unknown` with type guards when the type is truly unknown.
- Use discriminated unions for state management over boolean flags.
- Prefer small, focused functions under 30 lines. Extract helpers when logic grows.
- Use `readonly` for arrays and properties that should not be mutated.
- Prefer explicit return types on exported functions for documentation and faster type-checking.