🔰primitive wrapper

🚧 施工中

JS ⟩ value ⟩ primitive ⟩ wrapper

⭐️ 重點

undefined/null has no wrapper, can't call methods, no properties.

📘 手冊

• primitive wrapper object

• Object.assign()

👥 相關

• mixin: in Object.assign(), primitive (both target and sources) will be wrapped to objects.