AgentSkillsCN

use-optional-chaining

在访问可能为 null 或 undefined 的嵌套属性时，优先使用可选链操作符（?.），以确保安全访问。

SKILL.md
--- frontmatter
name: use-optional-chaining
description: Use optional chaining (?.) to safely access nested properties that might be null or undefined.

Use Optional Chaining

Pattern

Use ?. to safely access nested properties without explicit null checks.

✅ Good (Optional Chaining)

typescript
const modelName = settings?.transcription?.model?.name;
const firstItem = array?.[0];
const resultFunc = processor?.process?.();

❌ Bad (Manual Checks)

typescript
const modelName = settings && settings.transcription
  && settings.transcription.model
  && settings.transcription.model.name;

Syntax

Property Access

typescript
obj?.prop

Array/Computed Property

typescript
arr?.[0]
obj?.[dynamicKey]

Function Call

typescript
func?.()
callback?.(arg1, arg2)

When to Use

  • •Accessing nested object properties
  • •Calling functions that might not exist
  • •Working with optional data from APIs
  • •Handling potentially null/undefined values

Returns

Returns undefined if any part of the chain is null or undefined.