✅always use strict mode

it's best practice to use "strict mode".

JS ⟩ concepts ⟩ strict mode ⟩ always use strict mode

in strict mode：

• ✅eval has its own scope in strict mode.

• ✅ no accidental global variable in sloppy mode❗️

• ✅ no deplicate parameters❗. ( 👉 more ... )

• ✅ can't delete variables/functions. ( 👉 more ... )

• ✅ no octal literals ( 👉 more ... )

👥 相關

• parameter

• eval

• global variable

📗 參考

📘 手冊