🚧logical operator

🚧 under construction -> example

JS ⟩ statement ⟩ expression ⟩ operator ⟩ logical ⟩

• a && b ：returns a if a is falsy, otherwise returns b.

• a || b：returns a if a is truthy, otherwise returns b.

• a ?? b：returns a if a is non-nullish, otherwise returns b.

• !a：returns false if a is truthy, otherwise returns true.

🌟 table of operators

⭐️ 重點

• && and || can do short-circuiting.

• unlike && and ||, ! always returns true or false.

convert any value to Boolean.

!!x    // conversion: any -> true/false

👥 相關

• falsy / nullish

• conditional operator (?:)

• optional chaining (?., ?.[])

• nullish coalescing (??)

💈範例

replit：

// Some code

📗 參考

• JavaScript: The Definitive Guide ⟩ 4.10 Logical Expressions

📘 手冊