AgentSkillsCN

typescript

TypeScript 代码标准。在编写或审查 TypeScript 代码（.ts、.tsx 文件）时，可使用此标准。

SKILL.md
--- frontmatter
name: typescript
description: TypeScript code standards. Use when writing or reviewing TypeScript code (.ts, .tsx files).
user-invocable: false

TypeScript Standards

Imports

  • •ALWAYS import, NEVER require()
  • •Separate value imports and import type — types last
  • •Use @/ path alias when relative path has more than one ../
  • •NEVER import an entire namespace (import * as X) — destructure

Functions

  • •ALWAYS arrow functions: const fn = () => {} — NEVER function declarations
  • •Exception: exported module-level functions that need hoisting are acceptable

Types

  • •NEVER any — use proper types or unknown + type guards
  • •NEVER as casting — prefer type guards, generics, or Zod parsing (as const is OK)
  • •Prefer interface for object shapes, type for unions/intersections/utilities
  • •Discriminated unions over optional fields for variant types

Patterns

  • •Result pattern for data fetching: type Result<T, E = Error> = [E, null] | [null, T] — NEVER throw for expected errors
  • •Early returns over nested conditionals
  • •Destructure function params and object access
  • •Array.find inside a loop = build a Map first, O(1) lookups
  • •sort() mutates — use toSorted() or spread + sort
  • •Nullish coalescing (??) over logical OR (||) for defaults
  • •Optional chaining (?.) — but NEVER more than 3 levels deep; refactor the type instead
  • •const by default, let only when reassignment is necessary, NEVER var
  • •Prefer satisfies over as for type-checking without widening
  • •Use Map/Set over plain objects when keys are dynamic
  • •Enums: prefer as const objects over TypeScript enum